| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ovex | ⊢ ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) )  ∈  V | 
						
							| 2 |  | eqid | ⊢ ( 𝑏  ∈  ( fBas ‘ 𝑌 )  ↦  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) )  =  ( 𝑏  ∈  ( fBas ‘ 𝑌 )  ↦  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) ) | 
						
							| 3 | 1 2 | fnmpti | ⊢ ( 𝑏  ∈  ( fBas ‘ 𝑌 )  ↦  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) )  Fn  ( fBas ‘ 𝑌 ) | 
						
							| 4 |  | df-fm | ⊢  FilMap   =  ( 𝑥  ∈  V ,  𝑓  ∈  V  ↦  ( 𝑏  ∈  ( fBas ‘ dom  𝑓 )  ↦  ( 𝑥 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝑓  “  𝑦 ) ) ) ) ) | 
						
							| 5 | 4 | a1i | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →   FilMap   =  ( 𝑥  ∈  V ,  𝑓  ∈  V  ↦  ( 𝑏  ∈  ( fBas ‘ dom  𝑓 )  ↦  ( 𝑥 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝑓  “  𝑦 ) ) ) ) ) ) | 
						
							| 6 |  | dmeq | ⊢ ( 𝑓  =  𝐹  →  dom  𝑓  =  dom  𝐹 ) | 
						
							| 7 | 6 | adantl | ⊢ ( ( 𝑥  =  𝑋  ∧  𝑓  =  𝐹 )  →  dom  𝑓  =  dom  𝐹 ) | 
						
							| 8 |  | fdm | ⊢ ( 𝐹 : 𝑌 ⟶ 𝑋  →  dom  𝐹  =  𝑌 ) | 
						
							| 9 | 8 | 3ad2ant3 | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  dom  𝐹  =  𝑌 ) | 
						
							| 10 | 7 9 | sylan9eqr | ⊢ ( ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  ( 𝑥  =  𝑋  ∧  𝑓  =  𝐹 ) )  →  dom  𝑓  =  𝑌 ) | 
						
							| 11 | 10 | fveq2d | ⊢ ( ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  ( 𝑥  =  𝑋  ∧  𝑓  =  𝐹 ) )  →  ( fBas ‘ dom  𝑓 )  =  ( fBas ‘ 𝑌 ) ) | 
						
							| 12 |  | id | ⊢ ( 𝑥  =  𝑋  →  𝑥  =  𝑋 ) | 
						
							| 13 |  | imaeq1 | ⊢ ( 𝑓  =  𝐹  →  ( 𝑓  “  𝑦 )  =  ( 𝐹  “  𝑦 ) ) | 
						
							| 14 | 13 | mpteq2dv | ⊢ ( 𝑓  =  𝐹  →  ( 𝑦  ∈  𝑏  ↦  ( 𝑓  “  𝑦 ) )  =  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) | 
						
							| 15 | 14 | rneqd | ⊢ ( 𝑓  =  𝐹  →  ran  ( 𝑦  ∈  𝑏  ↦  ( 𝑓  “  𝑦 ) )  =  ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) | 
						
							| 16 | 12 15 | oveqan12d | ⊢ ( ( 𝑥  =  𝑋  ∧  𝑓  =  𝐹 )  →  ( 𝑥 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝑓  “  𝑦 ) ) )  =  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) ) | 
						
							| 17 | 16 | adantl | ⊢ ( ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  ( 𝑥  =  𝑋  ∧  𝑓  =  𝐹 ) )  →  ( 𝑥 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝑓  “  𝑦 ) ) )  =  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) ) | 
						
							| 18 | 11 17 | mpteq12dv | ⊢ ( ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  ( 𝑥  =  𝑋  ∧  𝑓  =  𝐹 ) )  →  ( 𝑏  ∈  ( fBas ‘ dom  𝑓 )  ↦  ( 𝑥 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝑓  “  𝑦 ) ) ) )  =  ( 𝑏  ∈  ( fBas ‘ 𝑌 )  ↦  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) ) ) | 
						
							| 19 |  | elex | ⊢ ( 𝑋  ∈  𝐴  →  𝑋  ∈  V ) | 
						
							| 20 | 19 | 3ad2ant1 | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  𝑋  ∈  V ) | 
						
							| 21 |  | fex2 | ⊢ ( ( 𝐹 : 𝑌 ⟶ 𝑋  ∧  𝑌  ∈  𝐵  ∧  𝑋  ∈  𝐴 )  →  𝐹  ∈  V ) | 
						
							| 22 | 21 | 3com13 | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  𝐹  ∈  V ) | 
						
							| 23 |  | fvex | ⊢ ( fBas ‘ 𝑌 )  ∈  V | 
						
							| 24 | 23 | mptex | ⊢ ( 𝑏  ∈  ( fBas ‘ 𝑌 )  ↦  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) )  ∈  V | 
						
							| 25 | 24 | a1i | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( 𝑏  ∈  ( fBas ‘ 𝑌 )  ↦  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) )  ∈  V ) | 
						
							| 26 | 5 18 20 22 25 | ovmpod | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( 𝑋  FilMap  𝐹 )  =  ( 𝑏  ∈  ( fBas ‘ 𝑌 )  ↦  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) ) ) | 
						
							| 27 | 26 | fneq1d | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( ( 𝑋  FilMap  𝐹 )  Fn  ( fBas ‘ 𝑌 )  ↔  ( 𝑏  ∈  ( fBas ‘ 𝑌 )  ↦  ( 𝑋 filGen ran  ( 𝑦  ∈  𝑏  ↦  ( 𝐹  “  𝑦 ) ) ) )  Fn  ( fBas ‘ 𝑌 ) ) ) | 
						
							| 28 | 3 27 | mpbiri | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( 𝑋  FilMap  𝐹 )  Fn  ( fBas ‘ 𝑌 ) ) | 
						
							| 29 |  | simpl1 | ⊢ ( ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑏  ∈  ( fBas ‘ 𝑌 ) )  →  𝑋  ∈  𝐴 ) | 
						
							| 30 |  | simpr | ⊢ ( ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑏  ∈  ( fBas ‘ 𝑌 ) )  →  𝑏  ∈  ( fBas ‘ 𝑌 ) ) | 
						
							| 31 |  | simpl3 | ⊢ ( ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑏  ∈  ( fBas ‘ 𝑌 ) )  →  𝐹 : 𝑌 ⟶ 𝑋 ) | 
						
							| 32 |  | fmfil | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑏  ∈  ( fBas ‘ 𝑌 )  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( ( 𝑋  FilMap  𝐹 ) ‘ 𝑏 )  ∈  ( Fil ‘ 𝑋 ) ) | 
						
							| 33 | 29 30 31 32 | syl3anc | ⊢ ( ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  ∧  𝑏  ∈  ( fBas ‘ 𝑌 ) )  →  ( ( 𝑋  FilMap  𝐹 ) ‘ 𝑏 )  ∈  ( Fil ‘ 𝑋 ) ) | 
						
							| 34 | 33 | ralrimiva | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ∀ 𝑏  ∈  ( fBas ‘ 𝑌 ) ( ( 𝑋  FilMap  𝐹 ) ‘ 𝑏 )  ∈  ( Fil ‘ 𝑋 ) ) | 
						
							| 35 |  | ffnfv | ⊢ ( ( 𝑋  FilMap  𝐹 ) : ( fBas ‘ 𝑌 ) ⟶ ( Fil ‘ 𝑋 )  ↔  ( ( 𝑋  FilMap  𝐹 )  Fn  ( fBas ‘ 𝑌 )  ∧  ∀ 𝑏  ∈  ( fBas ‘ 𝑌 ) ( ( 𝑋  FilMap  𝐹 ) ‘ 𝑏 )  ∈  ( Fil ‘ 𝑋 ) ) ) | 
						
							| 36 | 28 34 35 | sylanbrc | ⊢ ( ( 𝑋  ∈  𝐴  ∧  𝑌  ∈  𝐵  ∧  𝐹 : 𝑌 ⟶ 𝑋 )  →  ( 𝑋  FilMap  𝐹 ) : ( fBas ‘ 𝑌 ) ⟶ ( Fil ‘ 𝑋 ) ) |