| Step | Hyp | Ref | Expression | 
						
							| 1 |  | poimir.0 | ⊢ ( 𝜑  →  𝑁  ∈  ℕ ) | 
						
							| 2 |  | poimirlem22.s | ⊢ 𝑆  =  { 𝑡  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) )  ∣  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) } | 
						
							| 3 |  | poimirlem22.1 | ⊢ ( 𝜑  →  𝐹 : ( 0 ... ( 𝑁  −  1 ) ) ⟶ ( ( 0 ... 𝐾 )  ↑m  ( 1 ... 𝑁 ) ) ) | 
						
							| 4 |  | poimirlem22.2 | ⊢ ( 𝜑  →  𝑇  ∈  𝑆 ) | 
						
							| 5 |  | poimirlem15.3 | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... ( 𝑁  −  1 ) ) ) | 
						
							| 6 |  | elrabi | ⊢ ( 𝑇  ∈  { 𝑡  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) )  ∣  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) }  →  𝑇  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) ) ) | 
						
							| 7 | 6 2 | eleq2s | ⊢ ( 𝑇  ∈  𝑆  →  𝑇  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) ) ) | 
						
							| 8 | 4 7 | syl | ⊢ ( 𝜑  →  𝑇  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) ) ) | 
						
							| 9 |  | xp1st | ⊢ ( 𝑇  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) )  →  ( 1st  ‘ 𝑇 )  ∈  ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } ) ) | 
						
							| 10 |  | xp1st | ⊢ ( ( 1st  ‘ 𝑇 )  ∈  ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  →  ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∈  ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) ) ) | 
						
							| 11 | 8 9 10 | 3syl | ⊢ ( 𝜑  →  ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∈  ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) ) ) | 
						
							| 12 |  | xp2nd | ⊢ ( ( 1st  ‘ 𝑇 )  ∈  ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  →  ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∈  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } ) | 
						
							| 13 | 8 9 12 | 3syl | ⊢ ( 𝜑  →  ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∈  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } ) | 
						
							| 14 |  | fvex | ⊢ ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∈  V | 
						
							| 15 |  | f1oeq1 | ⊢ ( 𝑓  =  ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  →  ( 𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 )  ↔  ( 2nd  ‘ ( 1st  ‘ 𝑇 ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) ) | 
						
							| 16 | 14 15 | elab | ⊢ ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∈  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) }  ↔  ( 2nd  ‘ ( 1st  ‘ 𝑇 ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) | 
						
							| 17 | 13 16 | sylib | ⊢ ( 𝜑  →  ( 2nd  ‘ ( 1st  ‘ 𝑇 ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) | 
						
							| 18 |  | elfznn | ⊢ ( ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... ( 𝑁  −  1 ) )  →  ( 2nd  ‘ 𝑇 )  ∈  ℕ ) | 
						
							| 19 | 5 18 | syl | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ∈  ℕ ) | 
						
							| 20 | 19 | nnred | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ∈  ℝ ) | 
						
							| 21 | 20 | ltp1d | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  <  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) | 
						
							| 22 | 20 21 | ltned | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ≠  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) | 
						
							| 23 | 22 | necomd | ⊢ ( 𝜑  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≠  ( 2nd  ‘ 𝑇 ) ) | 
						
							| 24 |  | fvex | ⊢ ( 2nd  ‘ 𝑇 )  ∈  V | 
						
							| 25 |  | ovex | ⊢ ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  V | 
						
							| 26 |  | f1oprg | ⊢ ( ( ( ( 2nd  ‘ 𝑇 )  ∈  V  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  V )  ∧  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  V  ∧  ( 2nd  ‘ 𝑇 )  ∈  V ) )  →  ( ( ( 2nd  ‘ 𝑇 )  ≠  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≠  ( 2nd  ‘ 𝑇 ) )  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) } ) ) | 
						
							| 27 | 24 25 25 24 26 | mp4an | ⊢ ( ( ( 2nd  ‘ 𝑇 )  ≠  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≠  ( 2nd  ‘ 𝑇 ) )  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) } ) | 
						
							| 28 | 22 23 27 | syl2anc | ⊢ ( 𝜑  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) } ) | 
						
							| 29 |  | prcom | ⊢ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) }  =  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } | 
						
							| 30 |  | f1oeq3 | ⊢ ( { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) }  =  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) }  ↔  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 31 | 29 30 | ax-mp | ⊢ ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) }  ↔  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 32 | 28 31 | sylib | ⊢ ( 𝜑  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 33 |  | f1oi | ⊢ (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) : ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) –1-1-onto→ ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 34 |  | disjdif | ⊢ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ∅ | 
						
							| 35 |  | f1oun | ⊢ ( ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∧  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) : ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) –1-1-onto→ ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  ∧  ( ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ∅  ∧  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ∅ ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) –1-1-onto→ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 36 | 34 34 35 | mpanr12 | ⊢ ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∧  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) : ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) –1-1-onto→ ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) –1-1-onto→ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 37 | 32 33 36 | sylancl | ⊢ ( 𝜑  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) –1-1-onto→ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 38 | 1 | nncnd | ⊢ ( 𝜑  →  𝑁  ∈  ℂ ) | 
						
							| 39 |  | npcan1 | ⊢ ( 𝑁  ∈  ℂ  →  ( ( 𝑁  −  1 )  +  1 )  =  𝑁 ) | 
						
							| 40 | 38 39 | syl | ⊢ ( 𝜑  →  ( ( 𝑁  −  1 )  +  1 )  =  𝑁 ) | 
						
							| 41 | 1 | nnzd | ⊢ ( 𝜑  →  𝑁  ∈  ℤ ) | 
						
							| 42 |  | peano2zm | ⊢ ( 𝑁  ∈  ℤ  →  ( 𝑁  −  1 )  ∈  ℤ ) | 
						
							| 43 | 41 42 | syl | ⊢ ( 𝜑  →  ( 𝑁  −  1 )  ∈  ℤ ) | 
						
							| 44 |  | uzid | ⊢ ( ( 𝑁  −  1 )  ∈  ℤ  →  ( 𝑁  −  1 )  ∈  ( ℤ≥ ‘ ( 𝑁  −  1 ) ) ) | 
						
							| 45 |  | peano2uz | ⊢ ( ( 𝑁  −  1 )  ∈  ( ℤ≥ ‘ ( 𝑁  −  1 ) )  →  ( ( 𝑁  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ ( 𝑁  −  1 ) ) ) | 
						
							| 46 | 43 44 45 | 3syl | ⊢ ( 𝜑  →  ( ( 𝑁  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ ( 𝑁  −  1 ) ) ) | 
						
							| 47 | 40 46 | eqeltrrd | ⊢ ( 𝜑  →  𝑁  ∈  ( ℤ≥ ‘ ( 𝑁  −  1 ) ) ) | 
						
							| 48 |  | fzss2 | ⊢ ( 𝑁  ∈  ( ℤ≥ ‘ ( 𝑁  −  1 ) )  →  ( 1 ... ( 𝑁  −  1 ) )  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 49 | 47 48 | syl | ⊢ ( 𝜑  →  ( 1 ... ( 𝑁  −  1 ) )  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 50 | 49 5 | sseldd | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... 𝑁 ) ) | 
						
							| 51 | 19 | peano2nnd | ⊢ ( 𝜑  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℕ ) | 
						
							| 52 | 43 | zred | ⊢ ( 𝜑  →  ( 𝑁  −  1 )  ∈  ℝ ) | 
						
							| 53 | 1 | nnred | ⊢ ( 𝜑  →  𝑁  ∈  ℝ ) | 
						
							| 54 |  | elfzle2 | ⊢ ( ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... ( 𝑁  −  1 ) )  →  ( 2nd  ‘ 𝑇 )  ≤  ( 𝑁  −  1 ) ) | 
						
							| 55 | 5 54 | syl | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ≤  ( 𝑁  −  1 ) ) | 
						
							| 56 | 53 | ltm1d | ⊢ ( 𝜑  →  ( 𝑁  −  1 )  <  𝑁 ) | 
						
							| 57 | 20 52 53 55 56 | lelttrd | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  <  𝑁 ) | 
						
							| 58 | 19 | nnzd | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ∈  ℤ ) | 
						
							| 59 |  | zltp1le | ⊢ ( ( ( 2nd  ‘ 𝑇 )  ∈  ℤ  ∧  𝑁  ∈  ℤ )  →  ( ( 2nd  ‘ 𝑇 )  <  𝑁  ↔  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) ) | 
						
							| 60 | 58 41 59 | syl2anc | ⊢ ( 𝜑  →  ( ( 2nd  ‘ 𝑇 )  <  𝑁  ↔  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) ) | 
						
							| 61 | 57 60 | mpbid | ⊢ ( 𝜑  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) | 
						
							| 62 |  | fznn | ⊢ ( 𝑁  ∈  ℤ  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... 𝑁 )  ↔  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℕ  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) ) ) | 
						
							| 63 | 41 62 | syl | ⊢ ( 𝜑  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... 𝑁 )  ↔  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℕ  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) ) ) | 
						
							| 64 | 51 61 63 | mpbir2and | ⊢ ( 𝜑  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... 𝑁 ) ) | 
						
							| 65 |  | prssi | ⊢ ( ( ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... 𝑁 )  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... 𝑁 ) )  →  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 66 | 50 64 65 | syl2anc | ⊢ ( 𝜑  →  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 67 |  | undif | ⊢ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( 1 ... 𝑁 )  ↔  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( 1 ... 𝑁 ) ) | 
						
							| 68 | 66 67 | sylib | ⊢ ( 𝜑  →  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( 1 ... 𝑁 ) ) | 
						
							| 69 |  | f1oeq23 | ⊢ ( ( ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( 1 ... 𝑁 )  ∧  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( 1 ... 𝑁 ) )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) –1-1-onto→ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  ↔  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) ) | 
						
							| 70 | 68 68 69 | syl2anc | ⊢ ( 𝜑  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) –1-1-onto→ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  ↔  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) ) | 
						
							| 71 | 37 70 | mpbid | ⊢ ( 𝜑  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) | 
						
							| 72 |  | f1oco | ⊢ ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 )  ∧  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) | 
						
							| 73 | 17 71 72 | syl2anc | ⊢ ( 𝜑  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) | 
						
							| 74 |  | prex | ⊢ { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∈  V | 
						
							| 75 |  | ovex | ⊢ ( 1 ... 𝑁 )  ∈  V | 
						
							| 76 |  | difexg | ⊢ ( ( 1 ... 𝑁 )  ∈  V  →  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∈  V ) | 
						
							| 77 |  | resiexg | ⊢ ( ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∈  V  →  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  ∈  V ) | 
						
							| 78 | 75 76 77 | mp2b | ⊢ (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  ∈  V | 
						
							| 79 | 74 78 | unex | ⊢ ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  ∈  V | 
						
							| 80 | 14 79 | coex | ⊢ ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  ∈  V | 
						
							| 81 |  | f1oeq1 | ⊢ ( 𝑓  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  →  ( 𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 )  ↔  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) ) | 
						
							| 82 | 80 81 | elab | ⊢ ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  ∈  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) }  ↔  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) ) | 
						
							| 83 | 73 82 | sylibr | ⊢ ( 𝜑  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  ∈  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } ) | 
						
							| 84 |  | opelxpi | ⊢ ( ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∈  ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ∧  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  ∈  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  →  〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  ∈  ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } ) ) | 
						
							| 85 | 11 83 84 | syl2anc | ⊢ ( 𝜑  →  〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  ∈  ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } ) ) | 
						
							| 86 |  | fz1ssfz0 | ⊢ ( 1 ... 𝑁 )  ⊆  ( 0 ... 𝑁 ) | 
						
							| 87 | 49 86 | sstrdi | ⊢ ( 𝜑  →  ( 1 ... ( 𝑁  −  1 ) )  ⊆  ( 0 ... 𝑁 ) ) | 
						
							| 88 | 87 5 | sseldd | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ∈  ( 0 ... 𝑁 ) ) | 
						
							| 89 |  | opelxpi | ⊢ ( ( 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  ∈  ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ∧  ( 2nd  ‘ 𝑇 )  ∈  ( 0 ... 𝑁 ) )  →  〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) ) ) | 
						
							| 90 | 85 88 89 | syl2anc | ⊢ ( 𝜑  →  〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) ) ) | 
						
							| 91 |  | fveq2 | ⊢ ( 𝑡  =  𝑇  →  ( 2nd  ‘ 𝑡 )  =  ( 2nd  ‘ 𝑇 ) ) | 
						
							| 92 | 91 | breq2d | ⊢ ( 𝑡  =  𝑇  →  ( 𝑦  <  ( 2nd  ‘ 𝑡 )  ↔  𝑦  <  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 93 | 92 | ifbid | ⊢ ( 𝑡  =  𝑇  →  if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  =  if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) ) ) | 
						
							| 94 | 93 | csbeq1d | ⊢ ( 𝑡  =  𝑇  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 95 |  | 2fveq3 | ⊢ ( 𝑡  =  𝑇  →  ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  =  ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ) | 
						
							| 96 |  | 2fveq3 | ⊢ ( 𝑡  =  𝑇  →  ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  =  ( 2nd  ‘ ( 1st  ‘ 𝑇 ) ) ) | 
						
							| 97 | 96 | imaeq1d | ⊢ ( 𝑡  =  𝑇  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) ) ) | 
						
							| 98 | 97 | xpeq1d | ⊢ ( 𝑡  =  𝑇  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } ) ) | 
						
							| 99 | 96 | imaeq1d | ⊢ ( 𝑡  =  𝑇  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) ) ) | 
						
							| 100 | 99 | xpeq1d | ⊢ ( 𝑡  =  𝑇  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) | 
						
							| 101 | 98 100 | uneq12d | ⊢ ( 𝑡  =  𝑇  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 102 | 95 101 | oveq12d | ⊢ ( 𝑡  =  𝑇  →  ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 103 | 102 | csbeq2dv | ⊢ ( 𝑡  =  𝑇  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 104 | 94 103 | eqtrd | ⊢ ( 𝑡  =  𝑇  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 105 | 104 | mpteq2dv | ⊢ ( 𝑡  =  𝑇  →  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) )  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) | 
						
							| 106 | 105 | eqeq2d | ⊢ ( 𝑡  =  𝑇  →  ( 𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) )  ↔  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) ) | 
						
							| 107 | 106 2 | elrab2 | ⊢ ( 𝑇  ∈  𝑆  ↔  ( 𝑇  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) )  ∧  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) ) | 
						
							| 108 | 107 | simprbi | ⊢ ( 𝑇  ∈  𝑆  →  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) | 
						
							| 109 | 4 108 | syl | ⊢ ( 𝜑  →  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) | 
						
							| 110 |  | imaco | ⊢ ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... 𝑦 ) ) ) | 
						
							| 111 |  | f1ofn | ⊢ ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) }  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  Fn  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 112 | 28 111 | syl | ⊢ ( 𝜑  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  Fn  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 113 | 112 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  Fn  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 114 |  | incom | ⊢ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( 1 ... 𝑦 ) )  =  ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 115 |  | elfznn0 | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  𝑦  ∈  ℕ0 ) | 
						
							| 116 | 115 | nn0red | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  𝑦  ∈  ℝ ) | 
						
							| 117 |  | ltnle | ⊢ ( ( 𝑦  ∈  ℝ  ∧  ( 2nd  ‘ 𝑇 )  ∈  ℝ )  →  ( 𝑦  <  ( 2nd  ‘ 𝑇 )  ↔  ¬  ( 2nd  ‘ 𝑇 )  ≤  𝑦 ) ) | 
						
							| 118 | 116 20 117 | syl2anr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( 𝑦  <  ( 2nd  ‘ 𝑇 )  ↔  ¬  ( 2nd  ‘ 𝑇 )  ≤  𝑦 ) ) | 
						
							| 119 | 118 | biimpa | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ¬  ( 2nd  ‘ 𝑇 )  ≤  𝑦 ) | 
						
							| 120 |  | elfzle2 | ⊢ ( ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... 𝑦 )  →  ( 2nd  ‘ 𝑇 )  ≤  𝑦 ) | 
						
							| 121 | 119 120 | nsyl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ¬  ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... 𝑦 ) ) | 
						
							| 122 |  | disjsn | ⊢ ( ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  =  ∅  ↔  ¬  ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... 𝑦 ) ) | 
						
							| 123 | 121 122 | sylibr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  =  ∅ ) | 
						
							| 124 | 116 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  𝑦  ∈  ℝ ) | 
						
							| 125 | 20 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 2nd  ‘ 𝑇 )  ∈  ℝ ) | 
						
							| 126 | 51 | nnred | ⊢ ( 𝜑  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℝ ) | 
						
							| 127 | 126 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℝ ) | 
						
							| 128 |  | simpr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  𝑦  <  ( 2nd  ‘ 𝑇 ) ) | 
						
							| 129 | 21 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 2nd  ‘ 𝑇 )  <  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) | 
						
							| 130 | 124 125 127 128 129 | lttrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  𝑦  <  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) | 
						
							| 131 |  | ltnle | ⊢ ( ( 𝑦  ∈  ℝ  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℝ )  →  ( 𝑦  <  ( ( 2nd  ‘ 𝑇 )  +  1 )  ↔  ¬  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑦 ) ) | 
						
							| 132 | 116 126 131 | syl2anr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( 𝑦  <  ( ( 2nd  ‘ 𝑇 )  +  1 )  ↔  ¬  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑦 ) ) | 
						
							| 133 | 132 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 𝑦  <  ( ( 2nd  ‘ 𝑇 )  +  1 )  ↔  ¬  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑦 ) ) | 
						
							| 134 | 130 133 | mpbid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ¬  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑦 ) | 
						
							| 135 |  | elfzle2 | ⊢ ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... 𝑦 )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑦 ) | 
						
							| 136 | 134 135 | nsyl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ¬  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... 𝑦 ) ) | 
						
							| 137 |  | disjsn | ⊢ ( ( ( 1 ... 𝑦 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅  ↔  ¬  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... 𝑦 ) ) | 
						
							| 138 | 136 137 | sylibr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 1 ... 𝑦 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ ) | 
						
							| 139 | 123 138 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  ∪  ( ( 1 ... 𝑦 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ∅  ∪  ∅ ) ) | 
						
							| 140 |  | df-pr | ⊢ { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  =  ( { ( 2nd  ‘ 𝑇 ) }  ∪  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 141 | 140 | ineq2i | ⊢ ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ( ( 1 ... 𝑦 )  ∩  ( { ( 2nd  ‘ 𝑇 ) }  ∪  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 142 |  | indi | ⊢ ( ( 1 ... 𝑦 )  ∩  ( { ( 2nd  ‘ 𝑇 ) }  ∪  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  ∪  ( ( 1 ... 𝑦 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 143 | 141 142 | eqtr2i | ⊢ ( ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  ∪  ( ( 1 ... 𝑦 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 144 |  | un0 | ⊢ ( ∅  ∪  ∅ )  =  ∅ | 
						
							| 145 | 139 143 144 | 3eqtr3g | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ ) | 
						
							| 146 | 114 145 | eqtrid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( 1 ... 𝑦 ) )  =  ∅ ) | 
						
							| 147 |  | fnimadisj | ⊢ ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  Fn  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∧  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( 1 ... 𝑦 ) )  =  ∅ )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... 𝑦 ) )  =  ∅ ) | 
						
							| 148 | 113 146 147 | syl2anc | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... 𝑦 ) )  =  ∅ ) | 
						
							| 149 | 40 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( 𝑁  −  1 )  +  1 )  =  𝑁 ) | 
						
							| 150 |  | elfzuz3 | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( 𝑁  −  1 )  ∈  ( ℤ≥ ‘ 𝑦 ) ) | 
						
							| 151 |  | peano2uz | ⊢ ( ( 𝑁  −  1 )  ∈  ( ℤ≥ ‘ 𝑦 )  →  ( ( 𝑁  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ 𝑦 ) ) | 
						
							| 152 | 150 151 | syl | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( 𝑁  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ 𝑦 ) ) | 
						
							| 153 | 152 | adantl | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( 𝑁  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ 𝑦 ) ) | 
						
							| 154 | 149 153 | eqeltrrd | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  𝑁  ∈  ( ℤ≥ ‘ 𝑦 ) ) | 
						
							| 155 |  | fzss2 | ⊢ ( 𝑁  ∈  ( ℤ≥ ‘ 𝑦 )  →  ( 1 ... 𝑦 )  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 156 |  | reldisj | ⊢ ( ( 1 ... 𝑦 )  ⊆  ( 1 ... 𝑁 )  →  ( ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅  ↔  ( 1 ... 𝑦 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 157 | 154 155 156 | 3syl | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅  ↔  ( 1 ... 𝑦 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 158 | 157 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( 1 ... 𝑦 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅  ↔  ( 1 ... 𝑦 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 159 | 145 158 | mpbid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 1 ... 𝑦 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 160 |  | resiima | ⊢ ( ( 1 ... 𝑦 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( 1 ... 𝑦 ) )  =  ( 1 ... 𝑦 ) ) | 
						
							| 161 | 159 160 | syl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( 1 ... 𝑦 ) )  =  ( 1 ... 𝑦 ) ) | 
						
							| 162 | 148 161 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... 𝑦 ) )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( 1 ... 𝑦 ) ) )  =  ( ∅  ∪  ( 1 ... 𝑦 ) ) ) | 
						
							| 163 |  | imaundir | ⊢ ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... 𝑦 ) )  =  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... 𝑦 ) )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( 1 ... 𝑦 ) ) ) | 
						
							| 164 |  | uncom | ⊢ ( ∅  ∪  ( 1 ... 𝑦 ) )  =  ( ( 1 ... 𝑦 )  ∪  ∅ ) | 
						
							| 165 |  | un0 | ⊢ ( ( 1 ... 𝑦 )  ∪  ∅ )  =  ( 1 ... 𝑦 ) | 
						
							| 166 | 164 165 | eqtr2i | ⊢ ( 1 ... 𝑦 )  =  ( ∅  ∪  ( 1 ... 𝑦 ) ) | 
						
							| 167 | 162 163 166 | 3eqtr4g | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... 𝑦 ) )  =  ( 1 ... 𝑦 ) ) | 
						
							| 168 | 167 | imaeq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... 𝑦 ) ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) ) ) | 
						
							| 169 | 110 168 | eqtrid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) ) ) | 
						
							| 170 | 169 | xpeq1d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } ) ) | 
						
							| 171 |  | imaco | ⊢ ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 172 |  | imaundir | ⊢ ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  =  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 173 |  | imassrn | ⊢ ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ⊆  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } | 
						
							| 174 | 173 | a1i | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ⊆  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } ) | 
						
							| 175 |  | fnima | ⊢ ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  Fn  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } ) | 
						
							| 176 | 28 111 175 | 3syl | ⊢ ( 𝜑  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } ) | 
						
							| 177 | 176 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } ) | 
						
							| 178 |  | elfzelz | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  𝑦  ∈  ℤ ) | 
						
							| 179 |  | zltp1le | ⊢ ( ( 𝑦  ∈  ℤ  ∧  ( 2nd  ‘ 𝑇 )  ∈  ℤ )  →  ( 𝑦  <  ( 2nd  ‘ 𝑇 )  ↔  ( 𝑦  +  1 )  ≤  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 180 | 178 58 179 | syl2anr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( 𝑦  <  ( 2nd  ‘ 𝑇 )  ↔  ( 𝑦  +  1 )  ≤  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 181 | 180 | biimpa | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 𝑦  +  1 )  ≤  ( 2nd  ‘ 𝑇 ) ) | 
						
							| 182 | 20 53 57 | ltled | ⊢ ( 𝜑  →  ( 2nd  ‘ 𝑇 )  ≤  𝑁 ) | 
						
							| 183 | 182 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 2nd  ‘ 𝑇 )  ≤  𝑁 ) | 
						
							| 184 | 58 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( 2nd  ‘ 𝑇 )  ∈  ℤ ) | 
						
							| 185 |  | nn0p1nn | ⊢ ( 𝑦  ∈  ℕ0  →  ( 𝑦  +  1 )  ∈  ℕ ) | 
						
							| 186 | 115 185 | syl | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( 𝑦  +  1 )  ∈  ℕ ) | 
						
							| 187 | 186 | nnzd | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( 𝑦  +  1 )  ∈  ℤ ) | 
						
							| 188 | 187 | adantl | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( 𝑦  +  1 )  ∈  ℤ ) | 
						
							| 189 | 41 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  𝑁  ∈  ℤ ) | 
						
							| 190 |  | elfz | ⊢ ( ( ( 2nd  ‘ 𝑇 )  ∈  ℤ  ∧  ( 𝑦  +  1 )  ∈  ℤ  ∧  𝑁  ∈  ℤ )  →  ( ( 2nd  ‘ 𝑇 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 )  ↔  ( ( 𝑦  +  1 )  ≤  ( 2nd  ‘ 𝑇 )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑁 ) ) ) | 
						
							| 191 | 184 188 189 190 | syl3anc | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( 2nd  ‘ 𝑇 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 )  ↔  ( ( 𝑦  +  1 )  ≤  ( 2nd  ‘ 𝑇 )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑁 ) ) ) | 
						
							| 192 | 191 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 2nd  ‘ 𝑇 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 )  ↔  ( ( 𝑦  +  1 )  ≤  ( 2nd  ‘ 𝑇 )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑁 ) ) ) | 
						
							| 193 | 181 183 192 | mpbir2and | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 2nd  ‘ 𝑇 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 ) ) | 
						
							| 194 |  | 1red | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  1  ∈  ℝ ) | 
						
							| 195 |  | ltle | ⊢ ( ( 𝑦  ∈  ℝ  ∧  ( 2nd  ‘ 𝑇 )  ∈  ℝ )  →  ( 𝑦  <  ( 2nd  ‘ 𝑇 )  →  𝑦  ≤  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 196 | 116 20 195 | syl2anr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( 𝑦  <  ( 2nd  ‘ 𝑇 )  →  𝑦  ≤  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 197 | 196 | imp | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  𝑦  ≤  ( 2nd  ‘ 𝑇 ) ) | 
						
							| 198 | 124 125 194 197 | leadd1dd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 𝑦  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) | 
						
							| 199 | 61 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) | 
						
							| 200 | 58 | peano2zd | ⊢ ( 𝜑  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℤ ) | 
						
							| 201 | 200 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℤ ) | 
						
							| 202 |  | elfz | ⊢ ( ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℤ  ∧  ( 𝑦  +  1 )  ∈  ℤ  ∧  𝑁  ∈  ℤ )  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 )  ↔  ( ( 𝑦  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) ) ) | 
						
							| 203 | 201 188 189 202 | syl3anc | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 )  ↔  ( ( 𝑦  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) ) ) | 
						
							| 204 | 203 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 )  ↔  ( ( 𝑦  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  𝑁 ) ) ) | 
						
							| 205 | 198 199 204 | mpbir2and | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 ) ) | 
						
							| 206 |  | prssi | ⊢ ( ( ( 2nd  ‘ 𝑇 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 )  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( ( 𝑦  +  1 ) ... 𝑁 ) )  →  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( ( 𝑦  +  1 ) ... 𝑁 ) ) | 
						
							| 207 | 193 205 206 | syl2anc | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( ( 𝑦  +  1 ) ... 𝑁 ) ) | 
						
							| 208 |  | imass2 | ⊢ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( ( 𝑦  +  1 ) ... 𝑁 )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 209 | 207 208 | syl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 210 | 177 209 | eqsstrrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ⊆  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 211 | 174 210 | eqssd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  =  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } ) | 
						
							| 212 |  | f1ofo | ⊢ ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –1-1-onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) }  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) } ) | 
						
							| 213 |  | forn | ⊢ ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } : { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } –onto→ { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) }  →  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  =  { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) } ) | 
						
							| 214 | 28 212 213 | 3syl | ⊢ ( 𝜑  →  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  =  { ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) } ) | 
						
							| 215 | 214 29 | eqtrdi | ⊢ ( 𝜑  →  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  =  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 216 | 215 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  =  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 217 | 211 216 | eqtrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  =  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 218 |  | undif | ⊢ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( ( 𝑦  +  1 ) ... 𝑁 )  ↔  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( 𝑦  +  1 ) ... 𝑁 ) ) | 
						
							| 219 | 207 218 | sylib | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( 𝑦  +  1 ) ... 𝑁 ) ) | 
						
							| 220 | 219 | imaeq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  =  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 221 |  | fnresi | ⊢ (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  Fn  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 222 |  | disjdifr | ⊢ ( ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ | 
						
							| 223 |  | fnimadisj | ⊢ ( ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  Fn  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∧  ( ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ ) | 
						
							| 224 | 221 222 223 | mp2an | ⊢ ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ | 
						
							| 225 | 224 | a1i | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ ) | 
						
							| 226 |  | nnuz | ⊢ ℕ  =  ( ℤ≥ ‘ 1 ) | 
						
							| 227 | 186 226 | eleqtrdi | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( 𝑦  +  1 )  ∈  ( ℤ≥ ‘ 1 ) ) | 
						
							| 228 |  | fzss1 | ⊢ ( ( 𝑦  +  1 )  ∈  ( ℤ≥ ‘ 1 )  →  ( ( 𝑦  +  1 ) ... 𝑁 )  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 229 | 227 228 | syl | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( 𝑦  +  1 ) ... 𝑁 )  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 230 | 229 | ssdifd | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 231 |  | resiima | ⊢ ( ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 232 | 230 231 | syl | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 233 | 232 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 234 | 225 233 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  =  ( ∅  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 235 |  | imaundi | ⊢ ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  =  ( ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 236 |  | uncom | ⊢ ( ∅  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∪  ∅ ) | 
						
							| 237 |  | un0 | ⊢ ( ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∪  ∅ )  =  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 238 | 236 237 | eqtr2i | ⊢ ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ( ∅  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 239 | 234 235 238 | 3eqtr4g | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  =  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 240 | 220 239 | eqtr3d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  =  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 241 | 217 240 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) )  =  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 242 | 172 241 | eqtrid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  =  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( ( 𝑦  +  1 ) ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 243 | 242 219 | eqtrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  =  ( ( 𝑦  +  1 ) ... 𝑁 ) ) | 
						
							| 244 | 243 | imaeq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 245 | 171 244 | eqtrid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 246 | 245 | xpeq1d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) | 
						
							| 247 | 170 246 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 248 | 247 | oveq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 249 |  | iftrue | ⊢ ( 𝑦  <  ( 2nd  ‘ 𝑇 )  →  if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  =  𝑦 ) | 
						
							| 250 | 249 | csbeq1d | ⊢ ( 𝑦  <  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ 𝑦  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 251 |  | vex | ⊢ 𝑦  ∈  V | 
						
							| 252 |  | oveq2 | ⊢ ( 𝑗  =  𝑦  →  ( 1 ... 𝑗 )  =  ( 1 ... 𝑦 ) ) | 
						
							| 253 | 252 | imaeq2d | ⊢ ( 𝑗  =  𝑦  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) ) ) | 
						
							| 254 | 253 | xpeq1d | ⊢ ( 𝑗  =  𝑦  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } ) ) | 
						
							| 255 |  | oveq1 | ⊢ ( 𝑗  =  𝑦  →  ( 𝑗  +  1 )  =  ( 𝑦  +  1 ) ) | 
						
							| 256 | 255 | oveq1d | ⊢ ( 𝑗  =  𝑦  →  ( ( 𝑗  +  1 ) ... 𝑁 )  =  ( ( 𝑦  +  1 ) ... 𝑁 ) ) | 
						
							| 257 | 256 | imaeq2d | ⊢ ( 𝑗  =  𝑦  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 258 | 257 | xpeq1d | ⊢ ( 𝑗  =  𝑦  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) | 
						
							| 259 | 254 258 | uneq12d | ⊢ ( 𝑗  =  𝑦  →  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 260 | 259 | oveq2d | ⊢ ( 𝑗  =  𝑦  →  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 261 | 251 260 | csbie | ⊢ ⦋ 𝑦  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 262 | 250 261 | eqtrdi | ⊢ ( 𝑦  <  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 263 | 262 | adantl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 264 | 249 | csbeq1d | ⊢ ( 𝑦  <  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ 𝑦  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 265 | 252 | imaeq2d | ⊢ ( 𝑗  =  𝑦  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) ) ) | 
						
							| 266 | 265 | xpeq1d | ⊢ ( 𝑗  =  𝑦  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } ) ) | 
						
							| 267 | 256 | imaeq2d | ⊢ ( 𝑗  =  𝑦  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) ) ) | 
						
							| 268 | 267 | xpeq1d | ⊢ ( 𝑗  =  𝑦  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) | 
						
							| 269 | 266 268 | uneq12d | ⊢ ( 𝑗  =  𝑦  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 270 | 269 | oveq2d | ⊢ ( 𝑗  =  𝑦  →  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 271 | 251 270 | csbie | ⊢ ⦋ 𝑦  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 272 | 264 271 | eqtrdi | ⊢ ( 𝑦  <  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 273 | 272 | adantl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑦 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑦  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 274 | 248 263 273 | 3eqtr4d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 275 |  | lenlt | ⊢ ( ( ( 2nd  ‘ 𝑇 )  ∈  ℝ  ∧  𝑦  ∈  ℝ )  →  ( ( 2nd  ‘ 𝑇 )  ≤  𝑦  ↔  ¬  𝑦  <  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 276 | 20 116 275 | syl2an | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( 2nd  ‘ 𝑇 )  ≤  𝑦  ↔  ¬  𝑦  <  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 277 | 276 | biimpar | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ¬  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( 2nd  ‘ 𝑇 )  ≤  𝑦 ) | 
						
							| 278 |  | imaco | ⊢ ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 279 |  | imaundir | ⊢ ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  =  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 280 |  | imassrn | ⊢ ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) )  ⊆  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } | 
						
							| 281 | 280 | a1i | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) )  ⊆  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } ) | 
						
							| 282 | 176 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } ) | 
						
							| 283 | 19 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 2nd  ‘ 𝑇 )  ∈  ℕ ) | 
						
							| 284 | 20 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 2nd  ‘ 𝑇 )  ∈  ℝ ) | 
						
							| 285 | 116 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  𝑦  ∈  ℝ ) | 
						
							| 286 | 186 | nnred | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( 𝑦  +  1 )  ∈  ℝ ) | 
						
							| 287 | 286 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 𝑦  +  1 )  ∈  ℝ ) | 
						
							| 288 |  | simpr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 2nd  ‘ 𝑇 )  ≤  𝑦 ) | 
						
							| 289 | 116 | lep1d | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  𝑦  ≤  ( 𝑦  +  1 ) ) | 
						
							| 290 | 289 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  𝑦  ≤  ( 𝑦  +  1 ) ) | 
						
							| 291 | 284 285 287 288 290 | letrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 2nd  ‘ 𝑇 )  ≤  ( 𝑦  +  1 ) ) | 
						
							| 292 |  | fznn | ⊢ ( ( 𝑦  +  1 )  ∈  ℤ  →  ( ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... ( 𝑦  +  1 ) )  ↔  ( ( 2nd  ‘ 𝑇 )  ∈  ℕ  ∧  ( 2nd  ‘ 𝑇 )  ≤  ( 𝑦  +  1 ) ) ) ) | 
						
							| 293 | 187 292 | syl | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... ( 𝑦  +  1 ) )  ↔  ( ( 2nd  ‘ 𝑇 )  ∈  ℕ  ∧  ( 2nd  ‘ 𝑇 )  ≤  ( 𝑦  +  1 ) ) ) ) | 
						
							| 294 | 293 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... ( 𝑦  +  1 ) )  ↔  ( ( 2nd  ‘ 𝑇 )  ∈  ℕ  ∧  ( 2nd  ‘ 𝑇 )  ≤  ( 𝑦  +  1 ) ) ) ) | 
						
							| 295 | 283 291 294 | mpbir2and | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... ( 𝑦  +  1 ) ) ) | 
						
							| 296 | 51 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℕ ) | 
						
							| 297 |  | 1red | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  1  ∈  ℝ ) | 
						
							| 298 | 284 285 297 288 | leadd1dd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  ( 𝑦  +  1 ) ) | 
						
							| 299 |  | fznn | ⊢ ( ( 𝑦  +  1 )  ∈  ℤ  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... ( 𝑦  +  1 ) )  ↔  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℕ  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  ( 𝑦  +  1 ) ) ) ) | 
						
							| 300 | 187 299 | syl | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... ( 𝑦  +  1 ) )  ↔  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℕ  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  ( 𝑦  +  1 ) ) ) ) | 
						
							| 301 | 300 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... ( 𝑦  +  1 ) )  ↔  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℕ  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ≤  ( 𝑦  +  1 ) ) ) ) | 
						
							| 302 | 296 298 301 | mpbir2and | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... ( 𝑦  +  1 ) ) ) | 
						
							| 303 |  | prssi | ⊢ ( ( ( 2nd  ‘ 𝑇 )  ∈  ( 1 ... ( 𝑦  +  1 ) )  ∧  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( 1 ... ( 𝑦  +  1 ) ) )  →  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( 1 ... ( 𝑦  +  1 ) ) ) | 
						
							| 304 | 295 302 303 | syl2anc | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( 1 ... ( 𝑦  +  1 ) ) ) | 
						
							| 305 |  | imass2 | ⊢ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( 1 ... ( 𝑦  +  1 ) )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 306 | 304 305 | syl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 307 | 282 306 | eqsstrrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ⊆  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 308 | 281 307 | eqssd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) )  =  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 } ) | 
						
							| 309 | 215 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ran  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  =  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 310 | 308 309 | eqtrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) )  =  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 311 |  | undif | ⊢ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ⊆  ( 1 ... ( 𝑦  +  1 ) )  ↔  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( 1 ... ( 𝑦  +  1 ) ) ) | 
						
							| 312 | 304 311 | sylib | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( 1 ... ( 𝑦  +  1 ) ) ) | 
						
							| 313 | 312 | imaeq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  =  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 314 | 224 | a1i | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ ) | 
						
							| 315 |  | eluzp1p1 | ⊢ ( ( 𝑁  −  1 )  ∈  ( ℤ≥ ‘ 𝑦 )  →  ( ( 𝑁  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ ( 𝑦  +  1 ) ) ) | 
						
							| 316 | 150 315 | syl | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( 𝑁  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ ( 𝑦  +  1 ) ) ) | 
						
							| 317 | 316 | adantl | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( 𝑁  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ ( 𝑦  +  1 ) ) ) | 
						
							| 318 | 149 317 | eqeltrrd | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  𝑁  ∈  ( ℤ≥ ‘ ( 𝑦  +  1 ) ) ) | 
						
							| 319 |  | fzss2 | ⊢ ( 𝑁  ∈  ( ℤ≥ ‘ ( 𝑦  +  1 ) )  →  ( 1 ... ( 𝑦  +  1 ) )  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 320 | 318 319 | syl | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( 1 ... ( 𝑦  +  1 ) )  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 321 | 320 | ssdifd | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 322 | 321 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 323 |  | resiima | ⊢ ( ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 324 | 322 323 | syl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 325 | 314 324 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  =  ( ∅  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 326 |  | imaundi | ⊢ ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  =  ( ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 327 |  | uncom | ⊢ ( ∅  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∪  ∅ ) | 
						
							| 328 |  | un0 | ⊢ ( ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  ∪  ∅ )  =  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 329 | 327 328 | eqtr2i | ⊢ ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ( ∅  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 330 | 325 326 329 | 3eqtr4g | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  =  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 331 | 313 330 | eqtr3d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  =  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 332 | 310 331 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( 1 ... ( 𝑦  +  1 ) ) )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) )  =  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 333 | 279 332 | eqtrid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  =  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∪  ( ( 1 ... ( 𝑦  +  1 ) )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 334 | 333 312 | eqtrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  =  ( 1 ... ( 𝑦  +  1 ) ) ) | 
						
							| 335 | 334 | imaeq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 336 | 278 335 | eqtrid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 337 | 336 | xpeq1d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } ) ) | 
						
							| 338 |  | imaco | ⊢ ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) ) | 
						
							| 339 | 112 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  Fn  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 340 |  | incom | ⊢ ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 341 | 126 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℝ ) | 
						
							| 342 | 186 | peano2nnd | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( 𝑦  +  1 )  +  1 )  ∈  ℕ ) | 
						
							| 343 | 342 | nnred | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( 𝑦  +  1 )  +  1 )  ∈  ℝ ) | 
						
							| 344 | 343 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 𝑦  +  1 )  +  1 )  ∈  ℝ ) | 
						
							| 345 | 21 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 2nd  ‘ 𝑇 )  <  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) | 
						
							| 346 | 116 | ltp1d | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  𝑦  <  ( 𝑦  +  1 ) ) | 
						
							| 347 | 346 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  𝑦  <  ( 𝑦  +  1 ) ) | 
						
							| 348 | 284 285 287 288 347 | lelttrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 2nd  ‘ 𝑇 )  <  ( 𝑦  +  1 ) ) | 
						
							| 349 | 284 287 297 348 | ltadd1dd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ 𝑇 )  +  1 )  <  ( ( 𝑦  +  1 )  +  1 ) ) | 
						
							| 350 | 284 341 344 345 349 | lttrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( 2nd  ‘ 𝑇 )  <  ( ( 𝑦  +  1 )  +  1 ) ) | 
						
							| 351 |  | ltnle | ⊢ ( ( ( 2nd  ‘ 𝑇 )  ∈  ℝ  ∧  ( ( 𝑦  +  1 )  +  1 )  ∈  ℝ )  →  ( ( 2nd  ‘ 𝑇 )  <  ( ( 𝑦  +  1 )  +  1 )  ↔  ¬  ( ( 𝑦  +  1 )  +  1 )  ≤  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 352 | 20 343 351 | syl2an | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( 2nd  ‘ 𝑇 )  <  ( ( 𝑦  +  1 )  +  1 )  ↔  ¬  ( ( 𝑦  +  1 )  +  1 )  ≤  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 353 | 352 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ 𝑇 )  <  ( ( 𝑦  +  1 )  +  1 )  ↔  ¬  ( ( 𝑦  +  1 )  +  1 )  ≤  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 354 | 350 353 | mpbid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ¬  ( ( 𝑦  +  1 )  +  1 )  ≤  ( 2nd  ‘ 𝑇 ) ) | 
						
							| 355 |  | elfzle1 | ⊢ ( ( 2nd  ‘ 𝑇 )  ∈  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  →  ( ( 𝑦  +  1 )  +  1 )  ≤  ( 2nd  ‘ 𝑇 ) ) | 
						
							| 356 | 354 355 | nsyl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ¬  ( 2nd  ‘ 𝑇 )  ∈  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 357 |  | disjsn | ⊢ ( ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  =  ∅  ↔  ¬  ( 2nd  ‘ 𝑇 )  ∈  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 358 | 356 357 | sylibr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  =  ∅ ) | 
						
							| 359 |  | ltnle | ⊢ ( ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ℝ  ∧  ( ( 𝑦  +  1 )  +  1 )  ∈  ℝ )  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  <  ( ( 𝑦  +  1 )  +  1 )  ↔  ¬  ( ( 𝑦  +  1 )  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) ) | 
						
							| 360 | 126 343 359 | syl2an | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  <  ( ( 𝑦  +  1 )  +  1 )  ↔  ¬  ( ( 𝑦  +  1 )  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) ) | 
						
							| 361 | 360 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( 2nd  ‘ 𝑇 )  +  1 )  <  ( ( 𝑦  +  1 )  +  1 )  ↔  ¬  ( ( 𝑦  +  1 )  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) ) | 
						
							| 362 | 349 361 | mpbid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ¬  ( ( 𝑦  +  1 )  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) | 
						
							| 363 |  | elfzle1 | ⊢ ( ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  →  ( ( 𝑦  +  1 )  +  1 )  ≤  ( ( 2nd  ‘ 𝑇 )  +  1 ) ) | 
						
							| 364 | 362 363 | nsyl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ¬  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 365 |  | disjsn | ⊢ ( ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅  ↔  ¬  ( ( 2nd  ‘ 𝑇 )  +  1 )  ∈  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 366 | 364 365 | sylibr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ ) | 
						
							| 367 | 358 366 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  ∪  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ∅  ∪  ∅ ) ) | 
						
							| 368 | 140 | ineq2i | ⊢ ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  ( { ( 2nd  ‘ 𝑇 ) }  ∪  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 369 |  | indi | ⊢ ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  ( { ( 2nd  ‘ 𝑇 ) }  ∪  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  ∪  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 370 | 368 369 | eqtr2i | ⊢ ( ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) } )  ∪  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  =  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) | 
						
							| 371 | 367 370 144 | 3eqtr3g | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅ ) | 
						
							| 372 | 340 371 | eqtrid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ∅ ) | 
						
							| 373 |  | fnimadisj | ⊢ ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  Fn  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∧  ( { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) }  ∩  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ∅ )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ∅ ) | 
						
							| 374 | 339 372 373 | syl2anc | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ∅ ) | 
						
							| 375 | 342 226 | eleqtrdi | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( 𝑦  +  1 )  +  1 )  ∈  ( ℤ≥ ‘ 1 ) ) | 
						
							| 376 |  | fzss1 | ⊢ ( ( ( 𝑦  +  1 )  +  1 )  ∈  ( ℤ≥ ‘ 1 )  →  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ⊆  ( 1 ... 𝑁 ) ) | 
						
							| 377 |  | reldisj | ⊢ ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ⊆  ( 1 ... 𝑁 )  →  ( ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅  ↔  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 378 | 375 376 377 | 3syl | ⊢ ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  →  ( ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅  ↔  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 379 | 378 | ad2antlr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∩  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  =  ∅  ↔  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) | 
						
							| 380 | 371 379 | mpbid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) | 
						
							| 381 |  | resiima | ⊢ ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ⊆  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 382 | 380 381 | syl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 383 | 374 382 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) )  =  ( ∅  ∪  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) ) | 
						
							| 384 |  | imaundir | ⊢ ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ∪  ( (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) ) | 
						
							| 385 |  | uncom | ⊢ ( ∅  ∪  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∪  ∅ ) | 
						
							| 386 |  | un0 | ⊢ ( ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  ∪  ∅ )  =  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) | 
						
							| 387 | 385 386 | eqtr2i | ⊢ ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 )  =  ( ∅  ∪  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 388 | 383 384 387 | 3eqtr4g | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 389 | 388 | imaeq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) ) | 
						
							| 390 | 338 389 | eqtrid | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) ) | 
						
							| 391 | 390 | xpeq1d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) | 
						
							| 392 | 337 391 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ( 2nd  ‘ 𝑇 )  ≤  𝑦 )  →  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 393 | 277 392 | syldan | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ¬  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 394 | 393 | oveq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ¬  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 395 |  | iffalse | ⊢ ( ¬  𝑦  <  ( 2nd  ‘ 𝑇 )  →  if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  =  ( 𝑦  +  1 ) ) | 
						
							| 396 | 395 | csbeq1d | ⊢ ( ¬  𝑦  <  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ ( 𝑦  +  1 )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 397 |  | ovex | ⊢ ( 𝑦  +  1 )  ∈  V | 
						
							| 398 |  | oveq2 | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( 1 ... 𝑗 )  =  ( 1 ... ( 𝑦  +  1 ) ) ) | 
						
							| 399 | 398 | imaeq2d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 400 | 399 | xpeq1d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } ) ) | 
						
							| 401 |  | oveq1 | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( 𝑗  +  1 )  =  ( ( 𝑦  +  1 )  +  1 ) ) | 
						
							| 402 | 401 | oveq1d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( 𝑗  +  1 ) ... 𝑁 )  =  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) | 
						
							| 403 | 402 | imaeq2d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) ) | 
						
							| 404 | 403 | xpeq1d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) | 
						
							| 405 | 400 404 | uneq12d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 406 | 405 | oveq2d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 407 | 397 406 | csbie | ⊢ ⦋ ( 𝑦  +  1 )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 408 | 396 407 | eqtrdi | ⊢ ( ¬  𝑦  <  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 409 | 408 | adantl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ¬  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 410 | 395 | csbeq1d | ⊢ ( ¬  𝑦  <  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ ( 𝑦  +  1 )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 411 | 398 | imaeq2d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) ) ) | 
						
							| 412 | 411 | xpeq1d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } ) ) | 
						
							| 413 | 402 | imaeq2d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) ) ) | 
						
							| 414 | 413 | xpeq1d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) | 
						
							| 415 | 412 414 | uneq12d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 416 | 415 | oveq2d | ⊢ ( 𝑗  =  ( 𝑦  +  1 )  →  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 417 | 397 416 | csbie | ⊢ ⦋ ( 𝑦  +  1 )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 418 | 410 417 | eqtrdi | ⊢ ( ¬  𝑦  <  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 419 | 418 | adantl | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ¬  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... ( 𝑦  +  1 ) ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( ( 𝑦  +  1 )  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 420 | 394 409 419 | 3eqtr4d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  ∧  ¬  𝑦  <  ( 2nd  ‘ 𝑇 ) )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 421 | 274 420 | pm2.61dan | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) ) )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 422 | 421 | mpteq2dva | ⊢ ( 𝜑  →  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) )  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) | 
						
							| 423 | 109 422 | eqtr4d | ⊢ ( 𝜑  →  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) | 
						
							| 424 |  | opex | ⊢ 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  ∈  V | 
						
							| 425 | 424 24 | op1std | ⊢ ( 𝑡  =  〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  →  ( 1st  ‘ 𝑡 )  =  〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ) | 
						
							| 426 | 424 24 | op2ndd | ⊢ ( 𝑡  =  〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  →  ( 2nd  ‘ 𝑡 )  =  ( 2nd  ‘ 𝑇 ) ) | 
						
							| 427 |  | breq2 | ⊢ ( ( 2nd  ‘ 𝑡 )  =  ( 2nd  ‘ 𝑇 )  →  ( 𝑦  <  ( 2nd  ‘ 𝑡 )  ↔  𝑦  <  ( 2nd  ‘ 𝑇 ) ) ) | 
						
							| 428 | 427 | ifbid | ⊢ ( ( 2nd  ‘ 𝑡 )  =  ( 2nd  ‘ 𝑇 )  →  if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  =  if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) ) ) | 
						
							| 429 | 428 | csbeq1d | ⊢ ( ( 2nd  ‘ 𝑡 )  =  ( 2nd  ‘ 𝑇 )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 430 |  | fvex | ⊢ ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∈  V | 
						
							| 431 | 430 80 | op1std | ⊢ ( ( 1st  ‘ 𝑡 )  =  〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  →  ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  =  ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ) | 
						
							| 432 | 430 80 | op2ndd | ⊢ ( ( 1st  ‘ 𝑡 )  =  〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  →  ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) ) | 
						
							| 433 |  | id | ⊢ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  =  ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  →  ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  =  ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ) | 
						
							| 434 |  | imaeq1 | ⊢ ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) ) ) | 
						
							| 435 | 434 | xpeq1d | ⊢ ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } ) ) | 
						
							| 436 |  | imaeq1 | ⊢ ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  →  ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  =  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) ) ) | 
						
							| 437 | 436 | xpeq1d | ⊢ ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  →  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } )  =  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) | 
						
							| 438 | 435 437 | uneq12d | ⊢ ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  →  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) )  =  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) | 
						
							| 439 | 433 438 | oveqan12d | ⊢ ( ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  =  ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∧  ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  =  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) )  →  ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 440 | 431 432 439 | syl2anc | ⊢ ( ( 1st  ‘ 𝑡 )  =  〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  →  ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 441 | 440 | csbeq2dv | ⊢ ( ( 1st  ‘ 𝑡 )  =  〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 442 | 429 441 | sylan9eqr | ⊢ ( ( ( 1st  ‘ 𝑡 )  =  〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉  ∧  ( 2nd  ‘ 𝑡 )  =  ( 2nd  ‘ 𝑇 ) )  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 443 | 425 426 442 | syl2anc | ⊢ ( 𝑡  =  〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  →  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) )  =  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) | 
						
							| 444 | 443 | mpteq2dv | ⊢ ( 𝑡  =  〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  →  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) )  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) | 
						
							| 445 | 444 | eqeq2d | ⊢ ( 𝑡  =  〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  →  ( 𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑡 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑡 ) )  ∘f   +  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( 2nd  ‘ ( 1st  ‘ 𝑡 ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) )  ↔  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) ) | 
						
							| 446 | 445 2 | elrab2 | ⊢ ( 〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  ∈  𝑆  ↔  ( 〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  ∈  ( ( ( ( 0 ..^ 𝐾 )  ↑m  ( 1 ... 𝑁 ) )  ×  { 𝑓  ∣  𝑓 : ( 1 ... 𝑁 ) –1-1-onto→ ( 1 ... 𝑁 ) } )  ×  ( 0 ... 𝑁 ) )  ∧  𝐹  =  ( 𝑦  ∈  ( 0 ... ( 𝑁  −  1 ) )  ↦  ⦋ if ( 𝑦  <  ( 2nd  ‘ 𝑇 ) ,  𝑦 ,  ( 𝑦  +  1 ) )  /  𝑗 ⦌ ( ( 1st  ‘ ( 1st  ‘ 𝑇 ) )  ∘f   +  ( ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( 1 ... 𝑗 ) )  ×  { 1 } )  ∪  ( ( ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) )  “  ( ( 𝑗  +  1 ) ... 𝑁 ) )  ×  { 0 } ) ) ) ) ) ) | 
						
							| 447 | 90 423 446 | sylanbrc | ⊢ ( 𝜑  →  〈 〈 ( 1st  ‘ ( 1st  ‘ 𝑇 ) ) ,  ( ( 2nd  ‘ ( 1st  ‘ 𝑇 ) )  ∘  ( { 〈 ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) 〉 ,  〈 ( ( 2nd  ‘ 𝑇 )  +  1 ) ,  ( 2nd  ‘ 𝑇 ) 〉 }  ∪  (  I   ↾  ( ( 1 ... 𝑁 )  ∖  { ( 2nd  ‘ 𝑇 ) ,  ( ( 2nd  ‘ 𝑇 )  +  1 ) } ) ) ) ) 〉 ,  ( 2nd  ‘ 𝑇 ) 〉  ∈  𝑆 ) |