| Step | Hyp | Ref | Expression | 
						
							| 1 |  | metakunt18.1 | ⊢ ( 𝜑  →  𝑀  ∈  ℕ ) | 
						
							| 2 |  | metakunt18.2 | ⊢ ( 𝜑  →  𝐼  ∈  ℕ ) | 
						
							| 3 |  | metakunt18.3 | ⊢ ( 𝜑  →  𝐼  ≤  𝑀 ) | 
						
							| 4 | 2 | nnred | ⊢ ( 𝜑  →  𝐼  ∈  ℝ ) | 
						
							| 5 | 4 | ltm1d | ⊢ ( 𝜑  →  ( 𝐼  −  1 )  <  𝐼 ) | 
						
							| 6 |  | fzdisj | ⊢ ( ( 𝐼  −  1 )  <  𝐼  →  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  ( 𝐼 ... ( 𝑀  −  1 ) ) )  =  ∅ ) | 
						
							| 7 | 5 6 | syl | ⊢ ( 𝜑  →  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  ( 𝐼 ... ( 𝑀  −  1 ) ) )  =  ∅ ) | 
						
							| 8 | 1 | nnzd | ⊢ ( 𝜑  →  𝑀  ∈  ℤ ) | 
						
							| 9 |  | fzsn | ⊢ ( 𝑀  ∈  ℤ  →  ( 𝑀 ... 𝑀 )  =  { 𝑀 } ) | 
						
							| 10 | 8 9 | syl | ⊢ ( 𝜑  →  ( 𝑀 ... 𝑀 )  =  { 𝑀 } ) | 
						
							| 11 | 10 | eqcomd | ⊢ ( 𝜑  →  { 𝑀 }  =  ( 𝑀 ... 𝑀 ) ) | 
						
							| 12 | 11 | ineq2d | ⊢ ( 𝜑  →  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  { 𝑀 } )  =  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) ) ) | 
						
							| 13 | 2 | nnzd | ⊢ ( 𝜑  →  𝐼  ∈  ℤ ) | 
						
							| 14 |  | zlem1lt | ⊢ ( ( 𝐼  ∈  ℤ  ∧  𝑀  ∈  ℤ )  →  ( 𝐼  ≤  𝑀  ↔  ( 𝐼  −  1 )  <  𝑀 ) ) | 
						
							| 15 | 13 8 14 | syl2anc | ⊢ ( 𝜑  →  ( 𝐼  ≤  𝑀  ↔  ( 𝐼  −  1 )  <  𝑀 ) ) | 
						
							| 16 | 3 15 | mpbid | ⊢ ( 𝜑  →  ( 𝐼  −  1 )  <  𝑀 ) | 
						
							| 17 |  | fzdisj | ⊢ ( ( 𝐼  −  1 )  <  𝑀  →  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) )  =  ∅ ) | 
						
							| 18 | 16 17 | syl | ⊢ ( 𝜑  →  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) )  =  ∅ ) | 
						
							| 19 | 12 18 | eqtrd | ⊢ ( 𝜑  →  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  { 𝑀 } )  =  ∅ ) | 
						
							| 20 | 11 | ineq2d | ⊢ ( 𝜑  →  ( ( 𝐼 ... ( 𝑀  −  1 ) )  ∩  { 𝑀 } )  =  ( ( 𝐼 ... ( 𝑀  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) ) ) | 
						
							| 21 | 1 | nnred | ⊢ ( 𝜑  →  𝑀  ∈  ℝ ) | 
						
							| 22 | 21 | ltm1d | ⊢ ( 𝜑  →  ( 𝑀  −  1 )  <  𝑀 ) | 
						
							| 23 |  | fzdisj | ⊢ ( ( 𝑀  −  1 )  <  𝑀  →  ( ( 𝐼 ... ( 𝑀  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) )  =  ∅ ) | 
						
							| 24 | 22 23 | syl | ⊢ ( 𝜑  →  ( ( 𝐼 ... ( 𝑀  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) )  =  ∅ ) | 
						
							| 25 | 20 24 | eqtrd | ⊢ ( 𝜑  →  ( ( 𝐼 ... ( 𝑀  −  1 ) )  ∩  { 𝑀 } )  =  ∅ ) | 
						
							| 26 | 7 19 25 | 3jca | ⊢ ( 𝜑  →  ( ( ( 1 ... ( 𝐼  −  1 ) )  ∩  ( 𝐼 ... ( 𝑀  −  1 ) ) )  =  ∅  ∧  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  { 𝑀 } )  =  ∅  ∧  ( ( 𝐼 ... ( 𝑀  −  1 ) )  ∩  { 𝑀 } )  =  ∅ ) ) | 
						
							| 27 |  | incom | ⊢ ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  ( 1 ... ( 𝑀  −  𝐼 ) ) )  =  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) ) ) | 
						
							| 28 | 27 | a1i | ⊢ ( 𝜑  →  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  ( 1 ... ( 𝑀  −  𝐼 ) ) )  =  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) ) ) ) | 
						
							| 29 | 21 4 | resubcld | ⊢ ( 𝜑  →  ( 𝑀  −  𝐼 )  ∈  ℝ ) | 
						
							| 30 | 29 | ltp1d | ⊢ ( 𝜑  →  ( 𝑀  −  𝐼 )  <  ( ( 𝑀  −  𝐼 )  +  1 ) ) | 
						
							| 31 |  | fzdisj | ⊢ ( ( 𝑀  −  𝐼 )  <  ( ( 𝑀  −  𝐼 )  +  1 )  →  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) ) )  =  ∅ ) | 
						
							| 32 | 30 31 | syl | ⊢ ( 𝜑  →  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) ) )  =  ∅ ) | 
						
							| 33 | 28 32 | eqtrd | ⊢ ( 𝜑  →  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  ( 1 ... ( 𝑀  −  𝐼 ) ) )  =  ∅ ) | 
						
							| 34 | 11 | ineq2d | ⊢ ( 𝜑  →  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  { 𝑀 } )  =  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) ) ) | 
						
							| 35 |  | fzdisj | ⊢ ( ( 𝑀  −  1 )  <  𝑀  →  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) )  =  ∅ ) | 
						
							| 36 | 22 35 | syl | ⊢ ( 𝜑  →  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  ( 𝑀 ... 𝑀 ) )  =  ∅ ) | 
						
							| 37 | 34 36 | eqtrd | ⊢ ( 𝜑  →  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  { 𝑀 } )  =  ∅ ) | 
						
							| 38 | 11 | ineq2d | ⊢ ( 𝜑  →  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  { 𝑀 } )  =  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  ( 𝑀 ... 𝑀 ) ) ) | 
						
							| 39 | 2 | nnrpd | ⊢ ( 𝜑  →  𝐼  ∈  ℝ+ ) | 
						
							| 40 | 21 39 | ltsubrpd | ⊢ ( 𝜑  →  ( 𝑀  −  𝐼 )  <  𝑀 ) | 
						
							| 41 |  | fzdisj | ⊢ ( ( 𝑀  −  𝐼 )  <  𝑀  →  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  ( 𝑀 ... 𝑀 ) )  =  ∅ ) | 
						
							| 42 | 40 41 | syl | ⊢ ( 𝜑  →  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  ( 𝑀 ... 𝑀 ) )  =  ∅ ) | 
						
							| 43 | 38 42 | eqtrd | ⊢ ( 𝜑  →  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  { 𝑀 } )  =  ∅ ) | 
						
							| 44 | 33 37 43 | 3jca | ⊢ ( 𝜑  →  ( ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  ( 1 ... ( 𝑀  −  𝐼 ) ) )  =  ∅  ∧  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  { 𝑀 } )  =  ∅  ∧  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  { 𝑀 } )  =  ∅ ) ) | 
						
							| 45 | 26 44 | jca | ⊢ ( 𝜑  →  ( ( ( ( 1 ... ( 𝐼  −  1 ) )  ∩  ( 𝐼 ... ( 𝑀  −  1 ) ) )  =  ∅  ∧  ( ( 1 ... ( 𝐼  −  1 ) )  ∩  { 𝑀 } )  =  ∅  ∧  ( ( 𝐼 ... ( 𝑀  −  1 ) )  ∩  { 𝑀 } )  =  ∅ )  ∧  ( ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  ( 1 ... ( 𝑀  −  𝐼 ) ) )  =  ∅  ∧  ( ( ( ( 𝑀  −  𝐼 )  +  1 ) ... ( 𝑀  −  1 ) )  ∩  { 𝑀 } )  =  ∅  ∧  ( ( 1 ... ( 𝑀  −  𝐼 ) )  ∩  { 𝑀 } )  =  ∅ ) ) ) |