| Step | Hyp | Ref | Expression | 
						
							| 1 |  | fmval | ⊢ ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( ( 𝑋  FilMap  𝐹 ) ‘ 𝐵 )  =  ( 𝑋 filGen ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) ) ) | 
						
							| 2 | 1 | eleq2d | ⊢ ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( 𝐴  ∈  ( ( 𝑋  FilMap  𝐹 ) ‘ 𝐵 )  ↔  𝐴  ∈  ( 𝑋 filGen ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) ) ) ) | 
						
							| 3 |  | eqid | ⊢ ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  =  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) | 
						
							| 4 | 3 | fbasrn | ⊢ ( ( 𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋  ∧  𝑋  ∈  𝐶 )  →  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  ∈  ( fBas ‘ 𝑋 ) ) | 
						
							| 5 | 4 | 3comr | ⊢ ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  ∈  ( fBas ‘ 𝑋 ) ) | 
						
							| 6 |  | elfg | ⊢ ( ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  ∈  ( fBas ‘ 𝑋 )  →  ( 𝐴  ∈  ( 𝑋 filGen ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) )  ↔  ( 𝐴  ⊆  𝑋  ∧  ∃ 𝑦  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) 𝑦  ⊆  𝐴 ) ) ) | 
						
							| 7 | 5 6 | syl | ⊢ ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( 𝐴  ∈  ( 𝑋 filGen ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) )  ↔  ( 𝐴  ⊆  𝑋  ∧  ∃ 𝑦  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) 𝑦  ⊆  𝐴 ) ) ) | 
						
							| 8 |  | simpr | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑥  ∈  𝐵 )  →  𝑥  ∈  𝐵 ) | 
						
							| 9 |  | eqid | ⊢ ( 𝐹  “  𝑥 )  =  ( 𝐹  “  𝑥 ) | 
						
							| 10 |  | imaeq2 | ⊢ ( 𝑡  =  𝑥  →  ( 𝐹  “  𝑡 )  =  ( 𝐹  “  𝑥 ) ) | 
						
							| 11 | 10 | rspceeqv | ⊢ ( ( 𝑥  ∈  𝐵  ∧  ( 𝐹  “  𝑥 )  =  ( 𝐹  “  𝑥 ) )  →  ∃ 𝑡  ∈  𝐵 ( 𝐹  “  𝑥 )  =  ( 𝐹  “  𝑡 ) ) | 
						
							| 12 | 8 9 11 | sylancl | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑥  ∈  𝐵 )  →  ∃ 𝑡  ∈  𝐵 ( 𝐹  “  𝑥 )  =  ( 𝐹  “  𝑡 ) ) | 
						
							| 13 |  | simpl1 | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑥  ∈  𝐵 )  →  𝑋  ∈  𝐶 ) | 
						
							| 14 |  | imassrn | ⊢ ( 𝐹  “  𝑥 )  ⊆  ran  𝐹 | 
						
							| 15 |  | frn | ⊢ ( 𝐹 : 𝑌 ⟶ 𝑋  →  ran  𝐹  ⊆  𝑋 ) | 
						
							| 16 | 15 | 3ad2ant3 | ⊢ ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ran  𝐹  ⊆  𝑋 ) | 
						
							| 17 | 16 | adantr | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑥  ∈  𝐵 )  →  ran  𝐹  ⊆  𝑋 ) | 
						
							| 18 | 14 17 | sstrid | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑥  ∈  𝐵 )  →  ( 𝐹  “  𝑥 )  ⊆  𝑋 ) | 
						
							| 19 | 13 18 | ssexd | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑥  ∈  𝐵 )  →  ( 𝐹  “  𝑥 )  ∈  V ) | 
						
							| 20 |  | eqid | ⊢ ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  =  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) | 
						
							| 21 | 20 | elrnmpt | ⊢ ( ( 𝐹  “  𝑥 )  ∈  V  →  ( ( 𝐹  “  𝑥 )  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  ↔  ∃ 𝑡  ∈  𝐵 ( 𝐹  “  𝑥 )  =  ( 𝐹  “  𝑡 ) ) ) | 
						
							| 22 | 19 21 | syl | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑥  ∈  𝐵 )  →  ( ( 𝐹  “  𝑥 )  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  ↔  ∃ 𝑡  ∈  𝐵 ( 𝐹  “  𝑥 )  =  ( 𝐹  “  𝑡 ) ) ) | 
						
							| 23 | 12 22 | mpbird | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑥  ∈  𝐵 )  →  ( 𝐹  “  𝑥 )  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) ) | 
						
							| 24 | 10 | cbvmptv | ⊢ ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  =  ( 𝑥  ∈  𝐵  ↦  ( 𝐹  “  𝑥 ) ) | 
						
							| 25 | 24 | elrnmpt | ⊢ ( 𝑦  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  →  ( 𝑦  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  ↔  ∃ 𝑥  ∈  𝐵 𝑦  =  ( 𝐹  “  𝑥 ) ) ) | 
						
							| 26 | 25 | ibi | ⊢ ( 𝑦  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) )  →  ∃ 𝑥  ∈  𝐵 𝑦  =  ( 𝐹  “  𝑥 ) ) | 
						
							| 27 | 26 | adantl | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑦  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) )  →  ∃ 𝑥  ∈  𝐵 𝑦  =  ( 𝐹  “  𝑥 ) ) | 
						
							| 28 |  | simpr | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑦  =  ( 𝐹  “  𝑥 ) )  →  𝑦  =  ( 𝐹  “  𝑥 ) ) | 
						
							| 29 | 28 | sseq1d | ⊢ ( ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑦  =  ( 𝐹  “  𝑥 ) )  →  ( 𝑦  ⊆  𝐴  ↔  ( 𝐹  “  𝑥 )  ⊆  𝐴 ) ) | 
						
							| 30 | 23 27 29 | rexxfrd | ⊢ ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( ∃ 𝑦  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) 𝑦  ⊆  𝐴  ↔  ∃ 𝑥  ∈  𝐵 ( 𝐹  “  𝑥 )  ⊆  𝐴 ) ) | 
						
							| 31 | 30 | anbi2d | ⊢ ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( ( 𝐴  ⊆  𝑋  ∧  ∃ 𝑦  ∈  ran  ( 𝑡  ∈  𝐵  ↦  ( 𝐹  “  𝑡 ) ) 𝑦  ⊆  𝐴 )  ↔  ( 𝐴  ⊆  𝑋  ∧  ∃ 𝑥  ∈  𝐵 ( 𝐹  “  𝑥 )  ⊆  𝐴 ) ) ) | 
						
							| 32 | 2 7 31 | 3bitrd | ⊢ ( ( 𝑋  ∈  𝐶  ∧  𝐵  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( 𝐴  ∈  ( ( 𝑋  FilMap  𝐹 ) ‘ 𝐵 )  ↔  ( 𝐴  ⊆  𝑋  ∧  ∃ 𝑥  ∈  𝐵 ( 𝐹  “  𝑥 )  ⊆  𝐴 ) ) ) |