| Step | Hyp | Ref | Expression | 
						
							| 1 |  | axlowdimlem10.1 | ⊢ 𝑄  =  ( { 〈 ( 𝐼  +  1 ) ,  1 〉 }  ∪  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ) | 
						
							| 2 | 1 | fveq1i | ⊢ ( 𝑄 ‘ 𝐾 )  =  ( ( { 〈 ( 𝐼  +  1 ) ,  1 〉 }  ∪  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ) ‘ 𝐾 ) | 
						
							| 3 |  | eldifsn | ⊢ ( 𝐾  ∈  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ↔  ( 𝐾  ∈  ( 1 ... 𝑁 )  ∧  𝐾  ≠  ( 𝐼  +  1 ) ) ) | 
						
							| 4 |  | disjdif | ⊢ ( { ( 𝐼  +  1 ) }  ∩  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) )  =  ∅ | 
						
							| 5 |  | ovex | ⊢ ( 𝐼  +  1 )  ∈  V | 
						
							| 6 |  | 1ex | ⊢ 1  ∈  V | 
						
							| 7 | 5 6 | fnsn | ⊢ { 〈 ( 𝐼  +  1 ) ,  1 〉 }  Fn  { ( 𝐼  +  1 ) } | 
						
							| 8 |  | c0ex | ⊢ 0  ∈  V | 
						
							| 9 | 8 | fconst | ⊢ ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) : ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) ⟶ { 0 } | 
						
							| 10 |  | ffn | ⊢ ( ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) : ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) ⟶ { 0 }  →  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } )  Fn  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) ) | 
						
							| 11 | 9 10 | ax-mp | ⊢ ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } )  Fn  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) | 
						
							| 12 |  | fvun2 | ⊢ ( ( { 〈 ( 𝐼  +  1 ) ,  1 〉 }  Fn  { ( 𝐼  +  1 ) }  ∧  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } )  Fn  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ∧  ( ( { ( 𝐼  +  1 ) }  ∩  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) )  =  ∅  ∧  𝐾  ∈  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) ) )  →  ( ( { 〈 ( 𝐼  +  1 ) ,  1 〉 }  ∪  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ) ‘ 𝐾 )  =  ( ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ‘ 𝐾 ) ) | 
						
							| 13 | 7 11 12 | mp3an12 | ⊢ ( ( ( { ( 𝐼  +  1 ) }  ∩  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) )  =  ∅  ∧  𝐾  ∈  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } ) )  →  ( ( { 〈 ( 𝐼  +  1 ) ,  1 〉 }  ∪  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ) ‘ 𝐾 )  =  ( ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ‘ 𝐾 ) ) | 
						
							| 14 | 4 13 | mpan | ⊢ ( 𝐾  ∈  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  →  ( ( { 〈 ( 𝐼  +  1 ) ,  1 〉 }  ∪  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ) ‘ 𝐾 )  =  ( ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ‘ 𝐾 ) ) | 
						
							| 15 | 8 | fvconst2 | ⊢ ( 𝐾  ∈  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  →  ( ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ‘ 𝐾 )  =  0 ) | 
						
							| 16 | 14 15 | eqtrd | ⊢ ( 𝐾  ∈  ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  →  ( ( { 〈 ( 𝐼  +  1 ) ,  1 〉 }  ∪  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ) ‘ 𝐾 )  =  0 ) | 
						
							| 17 | 3 16 | sylbir | ⊢ ( ( 𝐾  ∈  ( 1 ... 𝑁 )  ∧  𝐾  ≠  ( 𝐼  +  1 ) )  →  ( ( { 〈 ( 𝐼  +  1 ) ,  1 〉 }  ∪  ( ( ( 1 ... 𝑁 )  ∖  { ( 𝐼  +  1 ) } )  ×  { 0 } ) ) ‘ 𝐾 )  =  0 ) | 
						
							| 18 | 2 17 | eqtrid | ⊢ ( ( 𝐾  ∈  ( 1 ... 𝑁 )  ∧  𝐾  ≠  ( 𝐼  +  1 ) )  →  ( 𝑄 ‘ 𝐾 )  =  0 ) |