| Step | Hyp | Ref | Expression | 
						
							| 1 |  | seqomlem.a | ⊢ 𝑄  =  rec ( ( 𝑖  ∈  ω ,  𝑣  ∈  V  ↦  〈 suc  𝑖 ,  ( 𝑖 𝐹 𝑣 ) 〉 ) ,  〈 ∅ ,  (  I  ‘ 𝐼 ) 〉 ) | 
						
							| 2 |  | frfnom | ⊢ ( rec ( ( 𝑖  ∈  ω ,  𝑣  ∈  V  ↦  〈 suc  𝑖 ,  ( 𝑖 𝐹 𝑣 ) 〉 ) ,  〈 ∅ ,  (  I  ‘ 𝐼 ) 〉 )  ↾  ω )  Fn  ω | 
						
							| 3 | 1 | reseq1i | ⊢ ( 𝑄  ↾  ω )  =  ( rec ( ( 𝑖  ∈  ω ,  𝑣  ∈  V  ↦  〈 suc  𝑖 ,  ( 𝑖 𝐹 𝑣 ) 〉 ) ,  〈 ∅ ,  (  I  ‘ 𝐼 ) 〉 )  ↾  ω ) | 
						
							| 4 | 3 | fneq1i | ⊢ ( ( 𝑄  ↾  ω )  Fn  ω  ↔  ( rec ( ( 𝑖  ∈  ω ,  𝑣  ∈  V  ↦  〈 suc  𝑖 ,  ( 𝑖 𝐹 𝑣 ) 〉 ) ,  〈 ∅ ,  (  I  ‘ 𝐼 ) 〉 )  ↾  ω )  Fn  ω ) | 
						
							| 5 | 2 4 | mpbir | ⊢ ( 𝑄  ↾  ω )  Fn  ω | 
						
							| 6 |  | fvres | ⊢ ( 𝑏  ∈  ω  →  ( ( 𝑄  ↾  ω ) ‘ 𝑏 )  =  ( 𝑄 ‘ 𝑏 ) ) | 
						
							| 7 | 1 | seqomlem1 | ⊢ ( 𝑏  ∈  ω  →  ( 𝑄 ‘ 𝑏 )  =  〈 𝑏 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑏 ) ) 〉 ) | 
						
							| 8 | 6 7 | eqtrd | ⊢ ( 𝑏  ∈  ω  →  ( ( 𝑄  ↾  ω ) ‘ 𝑏 )  =  〈 𝑏 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑏 ) ) 〉 ) | 
						
							| 9 |  | fvex | ⊢ ( 2nd  ‘ ( 𝑄 ‘ 𝑏 ) )  ∈  V | 
						
							| 10 |  | opelxpi | ⊢ ( ( 𝑏  ∈  ω  ∧  ( 2nd  ‘ ( 𝑄 ‘ 𝑏 ) )  ∈  V )  →  〈 𝑏 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑏 ) ) 〉  ∈  ( ω  ×  V ) ) | 
						
							| 11 | 9 10 | mpan2 | ⊢ ( 𝑏  ∈  ω  →  〈 𝑏 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑏 ) ) 〉  ∈  ( ω  ×  V ) ) | 
						
							| 12 | 8 11 | eqeltrd | ⊢ ( 𝑏  ∈  ω  →  ( ( 𝑄  ↾  ω ) ‘ 𝑏 )  ∈  ( ω  ×  V ) ) | 
						
							| 13 | 12 | rgen | ⊢ ∀ 𝑏  ∈  ω ( ( 𝑄  ↾  ω ) ‘ 𝑏 )  ∈  ( ω  ×  V ) | 
						
							| 14 |  | ffnfv | ⊢ ( ( 𝑄  ↾  ω ) : ω ⟶ ( ω  ×  V )  ↔  ( ( 𝑄  ↾  ω )  Fn  ω  ∧  ∀ 𝑏  ∈  ω ( ( 𝑄  ↾  ω ) ‘ 𝑏 )  ∈  ( ω  ×  V ) ) ) | 
						
							| 15 | 5 13 14 | mpbir2an | ⊢ ( 𝑄  ↾  ω ) : ω ⟶ ( ω  ×  V ) | 
						
							| 16 |  | frn | ⊢ ( ( 𝑄  ↾  ω ) : ω ⟶ ( ω  ×  V )  →  ran  ( 𝑄  ↾  ω )  ⊆  ( ω  ×  V ) ) | 
						
							| 17 | 15 16 | ax-mp | ⊢ ran  ( 𝑄  ↾  ω )  ⊆  ( ω  ×  V ) | 
						
							| 18 |  | df-br | ⊢ ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  〈 𝑎 ,  𝑏 〉  ∈  ran  ( 𝑄  ↾  ω ) ) | 
						
							| 19 |  | fvelrnb | ⊢ ( ( 𝑄  ↾  ω )  Fn  ω  →  ( 〈 𝑎 ,  𝑏 〉  ∈  ran  ( 𝑄  ↾  ω )  ↔  ∃ 𝑐  ∈  ω ( ( 𝑄  ↾  ω ) ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 20 | 5 19 | ax-mp | ⊢ ( 〈 𝑎 ,  𝑏 〉  ∈  ran  ( 𝑄  ↾  ω )  ↔  ∃ 𝑐  ∈  ω ( ( 𝑄  ↾  ω ) ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉 ) | 
						
							| 21 |  | fvres | ⊢ ( 𝑐  ∈  ω  →  ( ( 𝑄  ↾  ω ) ‘ 𝑐 )  =  ( 𝑄 ‘ 𝑐 ) ) | 
						
							| 22 | 21 | eqeq1d | ⊢ ( 𝑐  ∈  ω  →  ( ( ( 𝑄  ↾  ω ) ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  ↔  ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 23 | 22 | rexbiia | ⊢ ( ∃ 𝑐  ∈  ω ( ( 𝑄  ↾  ω ) ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  ↔  ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉 ) | 
						
							| 24 | 18 20 23 | 3bitri | ⊢ ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉 ) | 
						
							| 25 | 1 | seqomlem1 | ⊢ ( 𝑐  ∈  ω  →  ( 𝑄 ‘ 𝑐 )  =  〈 𝑐 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑐 ) ) 〉 ) | 
						
							| 26 | 25 | adantl | ⊢ ( ( 𝑎  ∈  ω  ∧  𝑐  ∈  ω )  →  ( 𝑄 ‘ 𝑐 )  =  〈 𝑐 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑐 ) ) 〉 ) | 
						
							| 27 | 26 | eqeq1d | ⊢ ( ( 𝑎  ∈  ω  ∧  𝑐  ∈  ω )  →  ( ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  ↔  〈 𝑐 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑐 ) ) 〉  =  〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 28 |  | vex | ⊢ 𝑐  ∈  V | 
						
							| 29 |  | fvex | ⊢ ( 2nd  ‘ ( 𝑄 ‘ 𝑐 ) )  ∈  V | 
						
							| 30 | 28 29 | opth1 | ⊢ ( 〈 𝑐 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑐 ) ) 〉  =  〈 𝑎 ,  𝑏 〉  →  𝑐  =  𝑎 ) | 
						
							| 31 | 27 30 | biimtrdi | ⊢ ( ( 𝑎  ∈  ω  ∧  𝑐  ∈  ω )  →  ( ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  →  𝑐  =  𝑎 ) ) | 
						
							| 32 |  | fveqeq2 | ⊢ ( 𝑐  =  𝑎  →  ( ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  ↔  ( 𝑄 ‘ 𝑎 )  =  〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 33 | 32 | biimpd | ⊢ ( 𝑐  =  𝑎  →  ( ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  →  ( 𝑄 ‘ 𝑎 )  =  〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 34 | 31 33 | syli | ⊢ ( ( 𝑎  ∈  ω  ∧  𝑐  ∈  ω )  →  ( ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  →  ( 𝑄 ‘ 𝑎 )  =  〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 35 |  | fveq2 | ⊢ ( ( 𝑄 ‘ 𝑎 )  =  〈 𝑎 ,  𝑏 〉  →  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  =  ( 2nd  ‘ 〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 36 |  | vex | ⊢ 𝑎  ∈  V | 
						
							| 37 |  | vex | ⊢ 𝑏  ∈  V | 
						
							| 38 | 36 37 | op2nd | ⊢ ( 2nd  ‘ 〈 𝑎 ,  𝑏 〉 )  =  𝑏 | 
						
							| 39 | 35 38 | eqtr2di | ⊢ ( ( 𝑄 ‘ 𝑎 )  =  〈 𝑎 ,  𝑏 〉  →  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) | 
						
							| 40 | 34 39 | syl6 | ⊢ ( ( 𝑎  ∈  ω  ∧  𝑐  ∈  ω )  →  ( ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  →  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) ) | 
						
							| 41 | 40 | rexlimdva | ⊢ ( 𝑎  ∈  ω  →  ( ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  →  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) ) | 
						
							| 42 | 1 | seqomlem1 | ⊢ ( 𝑎  ∈  ω  →  ( 𝑄 ‘ 𝑎 )  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉 ) | 
						
							| 43 |  | fveqeq2 | ⊢ ( 𝑐  =  𝑎  →  ( ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉  ↔  ( 𝑄 ‘ 𝑎 )  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉 ) ) | 
						
							| 44 | 43 | rspcev | ⊢ ( ( 𝑎  ∈  ω  ∧  ( 𝑄 ‘ 𝑎 )  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉 )  →  ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉 ) | 
						
							| 45 | 42 44 | mpdan | ⊢ ( 𝑎  ∈  ω  →  ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉 ) | 
						
							| 46 |  | opeq2 | ⊢ ( 𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  →  〈 𝑎 ,  𝑏 〉  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉 ) | 
						
							| 47 | 46 | eqeq2d | ⊢ ( 𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  →  ( ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  ↔  ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉 ) ) | 
						
							| 48 | 47 | rexbidv | ⊢ ( 𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  →  ( ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  ↔  ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) 〉 ) ) | 
						
							| 49 | 45 48 | syl5ibrcom | ⊢ ( 𝑎  ∈  ω  →  ( 𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  →  ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 50 | 41 49 | impbid | ⊢ ( 𝑎  ∈  ω  →  ( ∃ 𝑐  ∈  ω ( 𝑄 ‘ 𝑐 )  =  〈 𝑎 ,  𝑏 〉  ↔  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) ) | 
						
							| 51 | 24 50 | bitrid | ⊢ ( 𝑎  ∈  ω  →  ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) ) | 
						
							| 52 | 51 | alrimiv | ⊢ ( 𝑎  ∈  ω  →  ∀ 𝑏 ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) ) | 
						
							| 53 |  | fvex | ⊢ ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  ∈  V | 
						
							| 54 |  | eqeq2 | ⊢ ( 𝑐  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  →  ( 𝑏  =  𝑐  ↔  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) ) | 
						
							| 55 | 54 | bibi2d | ⊢ ( 𝑐  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  →  ( ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  𝑐 )  ↔  ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) ) ) | 
						
							| 56 | 55 | albidv | ⊢ ( 𝑐  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) )  →  ( ∀ 𝑏 ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  𝑐 )  ↔  ∀ 𝑏 ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) ) ) ) | 
						
							| 57 | 53 56 | spcev | ⊢ ( ∀ 𝑏 ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  ( 2nd  ‘ ( 𝑄 ‘ 𝑎 ) ) )  →  ∃ 𝑐 ∀ 𝑏 ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  𝑐 ) ) | 
						
							| 58 | 52 57 | syl | ⊢ ( 𝑎  ∈  ω  →  ∃ 𝑐 ∀ 𝑏 ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  𝑐 ) ) | 
						
							| 59 |  | eu6 | ⊢ ( ∃! 𝑏 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  ∃ 𝑐 ∀ 𝑏 ( 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏  ↔  𝑏  =  𝑐 ) ) | 
						
							| 60 | 58 59 | sylibr | ⊢ ( 𝑎  ∈  ω  →  ∃! 𝑏 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏 ) | 
						
							| 61 | 60 | rgen | ⊢ ∀ 𝑎  ∈  ω ∃! 𝑏 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏 | 
						
							| 62 |  | dff3 | ⊢ ( ran  ( 𝑄  ↾  ω ) : ω ⟶ V  ↔  ( ran  ( 𝑄  ↾  ω )  ⊆  ( ω  ×  V )  ∧  ∀ 𝑎  ∈  ω ∃! 𝑏 𝑎 ran  ( 𝑄  ↾  ω ) 𝑏 ) ) | 
						
							| 63 | 17 61 62 | mpbir2an | ⊢ ran  ( 𝑄  ↾  ω ) : ω ⟶ V | 
						
							| 64 |  | df-ima | ⊢ ( 𝑄  “  ω )  =  ran  ( 𝑄  ↾  ω ) | 
						
							| 65 | 64 | feq1i | ⊢ ( ( 𝑄  “  ω ) : ω ⟶ V  ↔  ran  ( 𝑄  ↾  ω ) : ω ⟶ V ) | 
						
							| 66 | 63 65 | mpbir | ⊢ ( 𝑄  “  ω ) : ω ⟶ V | 
						
							| 67 |  | dffn2 | ⊢ ( ( 𝑄  “  ω )  Fn  ω  ↔  ( 𝑄  “  ω ) : ω ⟶ V ) | 
						
							| 68 | 66 67 | mpbir | ⊢ ( 𝑄  “  ω )  Fn  ω |