Metamath Proof Explorer


Theorem dfrdg4

Description: A quantifier-free definition of the recursive definition generator. (Contributed by Scott Fenton, 17-Apr-2014) (Revised by Mario Carneiro, 19-Apr-2014) (Proof shortened by Peter Mazsa, 2-Oct-2022)

Ref Expression
Assertion dfrdg4 rec ( 𝐹 , 𝐴 ) = ∪ ( ( Funs ∩ ( ◡ Domain “ On ) ) ∖ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) )

Proof

Step Hyp Ref Expression
1 dfrdg3 ⊢ rec ( 𝐹 , 𝐴 ) = ∪ { 𝑓 ∣ ∃ 𝑥 ∈ On ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) }
2 an12 ⊢ ( ( 𝑥 ∈ On ∧ ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ↔ ( 𝑓 Fn 𝑥 ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
3 df-fn ⊢ ( 𝑓 Fn 𝑥 ↔ ( Fun 𝑓 ∧ dom 𝑓 = 𝑥 ) )
4 ancom ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 = 𝑥 ) ↔ ( dom 𝑓 = 𝑥 ∧ Fun 𝑓 ) )
5 eqcom ⊢ ( dom 𝑓 = 𝑥 ↔ 𝑥 = dom 𝑓 )
6 5 anbi1i ⊢ ( ( dom 𝑓 = 𝑥 ∧ Fun 𝑓 ) ↔ ( 𝑥 = dom 𝑓 ∧ Fun 𝑓 ) )
7 3 4 6 3bitri ⊢ ( 𝑓 Fn 𝑥 ↔ ( 𝑥 = dom 𝑓 ∧ Fun 𝑓 ) )
8 7 anbi1i ⊢ ( ( 𝑓 Fn 𝑥 ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ↔ ( ( 𝑥 = dom 𝑓 ∧ Fun 𝑓 ) ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
9 anass ⊢ ( ( ( 𝑥 = dom 𝑓 ∧ Fun 𝑓 ) ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ↔ ( 𝑥 = dom 𝑓 ∧ ( Fun 𝑓 ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ) )
10 2 8 9 3bitri ⊢ ( ( 𝑥 ∈ On ∧ ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ↔ ( 𝑥 = dom 𝑓 ∧ ( Fun 𝑓 ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ) )
11 10 exbii ⊢ ( ∃ 𝑥 ( 𝑥 ∈ On ∧ ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ↔ ∃ 𝑥 ( 𝑥 = dom 𝑓 ∧ ( Fun 𝑓 ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ) )
12 vex ⊢ 𝑓 ∈ V
13 12 dmex ⊢ dom 𝑓 ∈ V
14 eleq1 ⊢ ( 𝑥 = dom 𝑓 → ( 𝑥 ∈ On ↔ dom 𝑓 ∈ On ) )
15 raleq ⊢ ( 𝑥 = dom 𝑓 → ( ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ↔ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
16 14 15 anbi12d ⊢ ( 𝑥 = dom 𝑓 → ( ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ ( dom 𝑓 ∈ On ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
17 16 anbi2d ⊢ ( 𝑥 = dom 𝑓 → ( ( Fun 𝑓 ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ↔ ( Fun 𝑓 ∧ ( dom 𝑓 ∈ On ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ) )
18 13 17 ceqsexv ⊢ ( ∃ 𝑥 ( 𝑥 = dom 𝑓 ∧ ( Fun 𝑓 ∧ ( 𝑥 ∈ On ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ) ↔ ( Fun 𝑓 ∧ ( dom 𝑓 ∈ On ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
19 11 18 bitri ⊢ ( ∃ 𝑥 ( 𝑥 ∈ On ∧ ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) ↔ ( Fun 𝑓 ∧ ( dom 𝑓 ∈ On ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
20 df-rex ⊢ ( ∃ 𝑥 ∈ On ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ ∃ 𝑥 ( 𝑥 ∈ On ∧ ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
21 eldif ⊢ ( 𝑓 ∈ ( ( Funs ∩ ( ◡ Domain “ On ) ) ∖ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) ↔ ( 𝑓 ∈ ( Funs ∩ ( ◡ Domain “ On ) ) ∧ ¬ 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) )
22 elin ⊢ ( 𝑓 ∈ ( Funs ∩ ( ◡ Domain “ On ) ) ↔ ( 𝑓 ∈ Funs ∧ 𝑓 ∈ ( ◡ Domain “ On ) ) )
23 12 elfuns ⊢ ( 𝑓 ∈ Funs ↔ Fun 𝑓 )
24 12 elima ⊢ ( 𝑓 ∈ ( ◡ Domain “ On ) ↔ ∃ 𝑥 ∈ On 𝑥 ◡ Domain 𝑓 )
25 df-rex ⊢ ( ∃ 𝑥 ∈ On 𝑥 ◡ Domain 𝑓 ↔ ∃ 𝑥 ( 𝑥 ∈ On ∧ 𝑥 ◡ Domain 𝑓 ) )
26 vex ⊢ 𝑥 ∈ V
27 26 12 brcnv ⊢ ( 𝑥 ◡ Domain 𝑓 ↔ 𝑓 Domain 𝑥 )
28 12 26 brdomain ⊢ ( 𝑓 Domain 𝑥 ↔ 𝑥 = dom 𝑓 )
29 27 28 bitri ⊢ ( 𝑥 ◡ Domain 𝑓 ↔ 𝑥 = dom 𝑓 )
30 29 anbi1ci ⊢ ( ( 𝑥 ∈ On ∧ 𝑥 ◡ Domain 𝑓 ) ↔ ( 𝑥 = dom 𝑓 ∧ 𝑥 ∈ On ) )
31 30 exbii ⊢ ( ∃ 𝑥 ( 𝑥 ∈ On ∧ 𝑥 ◡ Domain 𝑓 ) ↔ ∃ 𝑥 ( 𝑥 = dom 𝑓 ∧ 𝑥 ∈ On ) )
32 13 14 ceqsexv ⊢ ( ∃ 𝑥 ( 𝑥 = dom 𝑓 ∧ 𝑥 ∈ On ) ↔ dom 𝑓 ∈ On )
33 31 32 bitri ⊢ ( ∃ 𝑥 ( 𝑥 ∈ On ∧ 𝑥 ◡ Domain 𝑓 ) ↔ dom 𝑓 ∈ On )
34 24 25 33 3bitri ⊢ ( 𝑓 ∈ ( ◡ Domain “ On ) ↔ dom 𝑓 ∈ On )
35 23 34 anbi12i ⊢ ( ( 𝑓 ∈ Funs ∧ 𝑓 ∈ ( ◡ Domain “ On ) ) ↔ ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) )
36 22 35 bitri ⊢ ( 𝑓 ∈ ( Funs ∩ ( ◡ Domain “ On ) ) ↔ ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) )
37 36 anbi1i ⊢ ( ( 𝑓 ∈ ( Funs ∩ ( ◡ Domain “ On ) ) ∧ ¬ 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) ↔ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) ∧ ¬ 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) )
38 brdif ⊢ ( 𝑓 ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) 𝑦 ↔ ( 𝑓 ( ◡ E ∘ Domain ) 𝑦 ∧ ¬ 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ) )
39 vex ⊢ 𝑦 ∈ V
40 12 39 brco ⊢ ( 𝑓 ( ◡ E ∘ Domain ) 𝑦 ↔ ∃ 𝑥 ( 𝑓 Domain 𝑥 ∧ 𝑥 ◡ E 𝑦 ) )
41 28 anbi1i ⊢ ( ( 𝑓 Domain 𝑥 ∧ 𝑥 ◡ E 𝑦 ) ↔ ( 𝑥 = dom 𝑓 ∧ 𝑥 ◡ E 𝑦 ) )
42 41 exbii ⊢ ( ∃ 𝑥 ( 𝑓 Domain 𝑥 ∧ 𝑥 ◡ E 𝑦 ) ↔ ∃ 𝑥 ( 𝑥 = dom 𝑓 ∧ 𝑥 ◡ E 𝑦 ) )
43 breq1 ⊢ ( 𝑥 = dom 𝑓 → ( 𝑥 ◡ E 𝑦 ↔ dom 𝑓 ◡ E 𝑦 ) )
44 13 43 ceqsexv ⊢ ( ∃ 𝑥 ( 𝑥 = dom 𝑓 ∧ 𝑥 ◡ E 𝑦 ) ↔ dom 𝑓 ◡ E 𝑦 )
45 42 44 bitri ⊢ ( ∃ 𝑥 ( 𝑓 Domain 𝑥 ∧ 𝑥 ◡ E 𝑦 ) ↔ dom 𝑓 ◡ E 𝑦 )
46 13 39 brcnv ⊢ ( dom 𝑓 ◡ E 𝑦 ↔ 𝑦 E dom 𝑓 )
47 13 epeli ⊢ ( 𝑦 E dom 𝑓 ↔ 𝑦 ∈ dom 𝑓 )
48 46 47 bitri ⊢ ( dom 𝑓 ◡ E 𝑦 ↔ 𝑦 ∈ dom 𝑓 )
49 40 45 48 3bitri ⊢ ( 𝑓 ( ◡ E ∘ Domain ) 𝑦 ↔ 𝑦 ∈ dom 𝑓 )
50 49 anbi1i ⊢ ( ( 𝑓 ( ◡ E ∘ Domain ) 𝑦 ∧ ¬ 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ) ↔ ( 𝑦 ∈ dom 𝑓 ∧ ¬ 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ) )
51 38 50 bitri ⊢ ( 𝑓 ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) 𝑦 ↔ ( 𝑦 ∈ dom 𝑓 ∧ ¬ 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ) )
52 onelon ⊢ ( ( dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → 𝑦 ∈ On )
53 52 3adant1 ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → 𝑦 ∈ On )
54 brun ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ↔ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) 𝑥 ∨ ⟨ 𝑓 , 𝑦 ⟩ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) 𝑥 ) )
55 brxp ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) 𝑥 ↔ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × { ∅ } ) ∧ 𝑥 ∈ { ∪ { 𝐴 } } ) )
56 opelxp ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × { ∅ } ) ↔ ( 𝑓 ∈ V ∧ 𝑦 ∈ { ∅ } ) )
57 12 56 mpbiran ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × { ∅ } ) ↔ 𝑦 ∈ { ∅ } )
58 velsn ⊢ ( 𝑦 ∈ { ∅ } ↔ 𝑦 = ∅ )
59 57 58 bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × { ∅ } ) ↔ 𝑦 = ∅ )
60 velsn ⊢ ( 𝑥 ∈ { ∪ { 𝐴 } } ↔ 𝑥 = ∪ { 𝐴 } )
61 59 60 anbi12i ⊢ ( ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × { ∅ } ) ∧ 𝑥 ∈ { ∪ { 𝐴 } } ) ↔ ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) )
62 55 61 bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) 𝑥 ↔ ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) )
63 brun ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) 𝑥 ↔ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) 𝑥 ∨ ⟨ 𝑓 , 𝑦 ⟩ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) 𝑥 ) )
64 26 brresi ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) 𝑥 ↔ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × Limits ) ∧ ⟨ 𝑓 , 𝑦 ⟩ ( Bigcup ∘ Img ) 𝑥 ) )
65 opelxp ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × Limits ) ↔ ( 𝑓 ∈ V ∧ 𝑦 ∈ Limits ) )
66 12 65 mpbiran ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × Limits ) ↔ 𝑦 ∈ Limits )
67 39 ellimits ⊢ ( 𝑦 ∈ Limits ↔ Lim 𝑦 )
68 66 67 bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × Limits ) ↔ Lim 𝑦 )
69 opex ⊢ ⟨ 𝑓 , 𝑦 ⟩ ∈ V
70 69 26 brco ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( Bigcup ∘ Img ) 𝑥 ↔ ∃ 𝑧 ( ⟨ 𝑓 , 𝑦 ⟩ Img 𝑧 ∧ 𝑧 Bigcup 𝑥 ) )
71 vex ⊢ 𝑧 ∈ V
72 12 39 71 brimg ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ Img 𝑧 ↔ 𝑧 = ( 𝑓 “ 𝑦 ) )
73 26 brbigcup ⊢ ( 𝑧 Bigcup 𝑥 ↔ ∪ 𝑧 = 𝑥 )
74 72 73 anbi12i ⊢ ( ( ⟨ 𝑓 , 𝑦 ⟩ Img 𝑧 ∧ 𝑧 Bigcup 𝑥 ) ↔ ( 𝑧 = ( 𝑓 “ 𝑦 ) ∧ ∪ 𝑧 = 𝑥 ) )
75 74 exbii ⊢ ( ∃ 𝑧 ( ⟨ 𝑓 , 𝑦 ⟩ Img 𝑧 ∧ 𝑧 Bigcup 𝑥 ) ↔ ∃ 𝑧 ( 𝑧 = ( 𝑓 “ 𝑦 ) ∧ ∪ 𝑧 = 𝑥 ) )
76 12 imaex ⊢ ( 𝑓 “ 𝑦 ) ∈ V
77 unieq ⊢ ( 𝑧 = ( 𝑓 “ 𝑦 ) → ∪ 𝑧 = ∪ ( 𝑓 “ 𝑦 ) )
78 77 eqeq1d ⊢ ( 𝑧 = ( 𝑓 “ 𝑦 ) → ( ∪ 𝑧 = 𝑥 ↔ ∪ ( 𝑓 “ 𝑦 ) = 𝑥 ) )
79 76 78 ceqsexv ⊢ ( ∃ 𝑧 ( 𝑧 = ( 𝑓 “ 𝑦 ) ∧ ∪ 𝑧 = 𝑥 ) ↔ ∪ ( 𝑓 “ 𝑦 ) = 𝑥 )
80 eqcom ⊢ ( ∪ ( 𝑓 “ 𝑦 ) = 𝑥 ↔ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) )
81 79 80 bitri ⊢ ( ∃ 𝑧 ( 𝑧 = ( 𝑓 “ 𝑦 ) ∧ ∪ 𝑧 = 𝑥 ) ↔ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) )
82 70 75 81 3bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( Bigcup ∘ Img ) 𝑥 ↔ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) )
83 68 82 anbi12i ⊢ ( ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × Limits ) ∧ ⟨ 𝑓 , 𝑦 ⟩ ( Bigcup ∘ Img ) 𝑥 ) ↔ ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) )
84 64 83 bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) 𝑥 ↔ ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) )
85 26 brresi ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) 𝑥 ↔ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × ran Succ ) ∧ ⟨ 𝑓 , 𝑦 ⟩ ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) 𝑥 ) )
86 opelxp ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × ran Succ ) ↔ ( 𝑓 ∈ V ∧ 𝑦 ∈ ran Succ ) )
87 12 86 mpbiran ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × ran Succ ) ↔ 𝑦 ∈ ran Succ )
88 39 elrn ⊢ ( 𝑦 ∈ ran Succ ↔ ∃ 𝑧 𝑧 Succ 𝑦 )
89 71 39 brsuccf ⊢ ( 𝑧 Succ 𝑦 ↔ 𝑦 = suc 𝑧 )
90 89 exbii ⊢ ( ∃ 𝑧 𝑧 Succ 𝑦 ↔ ∃ 𝑧 𝑦 = suc 𝑧 )
91 87 88 90 3bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × ran Succ ) ↔ ∃ 𝑧 𝑦 = suc 𝑧 )
92 69 26 brco ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) 𝑥 ↔ ∃ 𝑎 ( ⟨ 𝑓 , 𝑦 ⟩ ( Apply ∘ pprod ( I , Bigcup ) ) 𝑎 ∧ 𝑎 FullFun 𝐹 𝑥 ) )
93 vex ⊢ 𝑎 ∈ V
94 69 93 brco ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( Apply ∘ pprod ( I , Bigcup ) ) 𝑎 ↔ ∃ 𝑧 ( ⟨ 𝑓 , 𝑦 ⟩ pprod ( I , Bigcup ) 𝑧 ∧ 𝑧 Apply 𝑎 ) )
95 12 39 71 brpprod3a ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ pprod ( I , Bigcup ) 𝑧 ↔ ∃ 𝑎 ∃ 𝑏 ( 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ∧ 𝑓 I 𝑎 ∧ 𝑦 Bigcup 𝑏 ) )
96 3anrot ⊢ ( ( 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ∧ 𝑓 I 𝑎 ∧ 𝑦 Bigcup 𝑏 ) ↔ ( 𝑓 I 𝑎 ∧ 𝑦 Bigcup 𝑏 ∧ 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ) )
97 93 ideq ⊢ ( 𝑓 I 𝑎 ↔ 𝑓 = 𝑎 )
98 equcom ⊢ ( 𝑓 = 𝑎 ↔ 𝑎 = 𝑓 )
99 97 98 bitri ⊢ ( 𝑓 I 𝑎 ↔ 𝑎 = 𝑓 )
100 vex ⊢ 𝑏 ∈ V
101 100 brbigcup ⊢ ( 𝑦 Bigcup 𝑏 ↔ ∪ 𝑦 = 𝑏 )
102 eqcom ⊢ ( ∪ 𝑦 = 𝑏 ↔ 𝑏 = ∪ 𝑦 )
103 101 102 bitri ⊢ ( 𝑦 Bigcup 𝑏 ↔ 𝑏 = ∪ 𝑦 )
104 biid ⊢ ( 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ↔ 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ )
105 99 103 104 3anbi123i ⊢ ( ( 𝑓 I 𝑎 ∧ 𝑦 Bigcup 𝑏 ∧ 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ) ↔ ( 𝑎 = 𝑓 ∧ 𝑏 = ∪ 𝑦 ∧ 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ) )
106 96 105 bitri ⊢ ( ( 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ∧ 𝑓 I 𝑎 ∧ 𝑦 Bigcup 𝑏 ) ↔ ( 𝑎 = 𝑓 ∧ 𝑏 = ∪ 𝑦 ∧ 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ) )
107 106 2exbii ⊢ ( ∃ 𝑎 ∃ 𝑏 ( 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ∧ 𝑓 I 𝑎 ∧ 𝑦 Bigcup 𝑏 ) ↔ ∃ 𝑎 ∃ 𝑏 ( 𝑎 = 𝑓 ∧ 𝑏 = ∪ 𝑦 ∧ 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ) )
108 vuniex ⊢ ∪ 𝑦 ∈ V
109 opeq1 ⊢ ( 𝑎 = 𝑓 → ⟨ 𝑎 , 𝑏 ⟩ = ⟨ 𝑓 , 𝑏 ⟩ )
110 109 eqeq2d ⊢ ( 𝑎 = 𝑓 → ( 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ↔ 𝑧 = ⟨ 𝑓 , 𝑏 ⟩ ) )
111 opeq2 ⊢ ( 𝑏 = ∪ 𝑦 → ⟨ 𝑓 , 𝑏 ⟩ = ⟨ 𝑓 , ∪ 𝑦 ⟩ )
112 111 eqeq2d ⊢ ( 𝑏 = ∪ 𝑦 → ( 𝑧 = ⟨ 𝑓 , 𝑏 ⟩ ↔ 𝑧 = ⟨ 𝑓 , ∪ 𝑦 ⟩ ) )
113 12 108 110 112 ceqsex2v ⊢ ( ∃ 𝑎 ∃ 𝑏 ( 𝑎 = 𝑓 ∧ 𝑏 = ∪ 𝑦 ∧ 𝑧 = ⟨ 𝑎 , 𝑏 ⟩ ) ↔ 𝑧 = ⟨ 𝑓 , ∪ 𝑦 ⟩ )
114 95 107 113 3bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ pprod ( I , Bigcup ) 𝑧 ↔ 𝑧 = ⟨ 𝑓 , ∪ 𝑦 ⟩ )
115 114 anbi1i ⊢ ( ( ⟨ 𝑓 , 𝑦 ⟩ pprod ( I , Bigcup ) 𝑧 ∧ 𝑧 Apply 𝑎 ) ↔ ( 𝑧 = ⟨ 𝑓 , ∪ 𝑦 ⟩ ∧ 𝑧 Apply 𝑎 ) )
116 115 exbii ⊢ ( ∃ 𝑧 ( ⟨ 𝑓 , 𝑦 ⟩ pprod ( I , Bigcup ) 𝑧 ∧ 𝑧 Apply 𝑎 ) ↔ ∃ 𝑧 ( 𝑧 = ⟨ 𝑓 , ∪ 𝑦 ⟩ ∧ 𝑧 Apply 𝑎 ) )
117 opex ⊢ ⟨ 𝑓 , ∪ 𝑦 ⟩ ∈ V
118 breq1 ⊢ ( 𝑧 = ⟨ 𝑓 , ∪ 𝑦 ⟩ → ( 𝑧 Apply 𝑎 ↔ ⟨ 𝑓 , ∪ 𝑦 ⟩ Apply 𝑎 ) )
119 117 118 ceqsexv ⊢ ( ∃ 𝑧 ( 𝑧 = ⟨ 𝑓 , ∪ 𝑦 ⟩ ∧ 𝑧 Apply 𝑎 ) ↔ ⟨ 𝑓 , ∪ 𝑦 ⟩ Apply 𝑎 )
120 12 108 93 brapply ⊢ ( ⟨ 𝑓 , ∪ 𝑦 ⟩ Apply 𝑎 ↔ 𝑎 = ( 𝑓 ‘ ∪ 𝑦 ) )
121 119 120 bitri ⊢ ( ∃ 𝑧 ( 𝑧 = ⟨ 𝑓 , ∪ 𝑦 ⟩ ∧ 𝑧 Apply 𝑎 ) ↔ 𝑎 = ( 𝑓 ‘ ∪ 𝑦 ) )
122 94 116 121 3bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( Apply ∘ pprod ( I , Bigcup ) ) 𝑎 ↔ 𝑎 = ( 𝑓 ‘ ∪ 𝑦 ) )
123 93 26 brfullfun ⊢ ( 𝑎 FullFun 𝐹 𝑥 ↔ 𝑥 = ( 𝐹 ‘ 𝑎 ) )
124 122 123 anbi12i ⊢ ( ( ⟨ 𝑓 , 𝑦 ⟩ ( Apply ∘ pprod ( I , Bigcup ) ) 𝑎 ∧ 𝑎 FullFun 𝐹 𝑥 ) ↔ ( 𝑎 = ( 𝑓 ‘ ∪ 𝑦 ) ∧ 𝑥 = ( 𝐹 ‘ 𝑎 ) ) )
125 124 exbii ⊢ ( ∃ 𝑎 ( ⟨ 𝑓 , 𝑦 ⟩ ( Apply ∘ pprod ( I , Bigcup ) ) 𝑎 ∧ 𝑎 FullFun 𝐹 𝑥 ) ↔ ∃ 𝑎 ( 𝑎 = ( 𝑓 ‘ ∪ 𝑦 ) ∧ 𝑥 = ( 𝐹 ‘ 𝑎 ) ) )
126 fvex ⊢ ( 𝑓 ‘ ∪ 𝑦 ) ∈ V
127 fveq2 ⊢ ( 𝑎 = ( 𝑓 ‘ ∪ 𝑦 ) → ( 𝐹 ‘ 𝑎 ) = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) )
128 127 eqeq2d ⊢ ( 𝑎 = ( 𝑓 ‘ ∪ 𝑦 ) → ( 𝑥 = ( 𝐹 ‘ 𝑎 ) ↔ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) )
129 126 128 ceqsexv ⊢ ( ∃ 𝑎 ( 𝑎 = ( 𝑓 ‘ ∪ 𝑦 ) ∧ 𝑥 = ( 𝐹 ‘ 𝑎 ) ) ↔ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) )
130 92 125 129 3bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) 𝑥 ↔ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) )
131 91 130 anbi12i ⊢ ( ( ⟨ 𝑓 , 𝑦 ⟩ ∈ ( V × ran Succ ) ∧ ⟨ 𝑓 , 𝑦 ⟩ ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) 𝑥 ) ↔ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) )
132 85 131 bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) 𝑥 ↔ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) )
133 84 132 orbi12i ⊢ ( ( ⟨ 𝑓 , 𝑦 ⟩ ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) 𝑥 ∨ ⟨ 𝑓 , 𝑦 ⟩ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) 𝑥 ) ↔ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) )
134 63 133 bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) 𝑥 ↔ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) )
135 62 134 orbi12i ⊢ ( ( ⟨ 𝑓 , 𝑦 ⟩ ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) 𝑥 ∨ ⟨ 𝑓 , 𝑦 ⟩ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) 𝑥 ) ↔ ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
136 54 135 bitri ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ↔ ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
137 onzsl ⊢ ( 𝑦 ∈ On ↔ ( 𝑦 = ∅ ∨ ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 ∨ ( 𝑦 ∈ V ∧ Lim 𝑦 ) ) )
138 nlim0 ⊢ ¬ Lim ∅
139 limeq ⊢ ( 𝑦 = ∅ → ( Lim 𝑦 ↔ Lim ∅ ) )
140 138 139 mtbiri ⊢ ( 𝑦 = ∅ → ¬ Lim 𝑦 )
141 140 intnanrd ⊢ ( 𝑦 = ∅ → ¬ ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) )
142 nsuceq0 ⊢ suc 𝑧 ≠ ∅
143 neeq2 ⊢ ( 𝑦 = ∅ → ( suc 𝑧 ≠ 𝑦 ↔ suc 𝑧 ≠ ∅ ) )
144 142 143 mpbiri ⊢ ( 𝑦 = ∅ → suc 𝑧 ≠ 𝑦 )
145 144 necomd ⊢ ( 𝑦 = ∅ → 𝑦 ≠ suc 𝑧 )
146 145 neneqd ⊢ ( 𝑦 = ∅ → ¬ 𝑦 = suc 𝑧 )
147 146 nexdv ⊢ ( 𝑦 = ∅ → ¬ ∃ 𝑧 𝑦 = suc 𝑧 )
148 147 intnanrd ⊢ ( 𝑦 = ∅ → ¬ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) )
149 ioran ⊢ ( ¬ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ↔ ( ¬ ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∧ ¬ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) )
150 141 148 149 sylanbrc ⊢ ( 𝑦 = ∅ → ¬ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) )
151 orel2 ⊢ ( ¬ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ) )
152 150 151 syl ⊢ ( 𝑦 = ∅ → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ) )
153 iftrue ⊢ ( 𝑦 = ∅ → if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) = if ( 𝐴 ∈ V , 𝐴 , ∅ ) )
154 unisnif ⊢ ∪ { 𝐴 } = if ( 𝐴 ∈ V , 𝐴 , ∅ )
155 153 154 eqtr4di ⊢ ( 𝑦 = ∅ → if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) = ∪ { 𝐴 } )
156 155 eqeq2d ⊢ ( 𝑦 = ∅ → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ↔ 𝑥 = ∪ { 𝐴 } ) )
157 156 biimprd ⊢ ( 𝑦 = ∅ → ( 𝑥 = ∪ { 𝐴 } → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
158 157 adantld ⊢ ( 𝑦 = ∅ → ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
159 152 158 syld ⊢ ( 𝑦 = ∅ → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
160 156 biimpd ⊢ ( 𝑦 = ∅ → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → 𝑥 = ∪ { 𝐴 } ) )
161 160 anc2li ⊢ ( 𝑦 = ∅ → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ) )
162 orc ⊢ ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) → ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
163 161 162 syl6 ⊢ ( 𝑦 = ∅ → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
164 159 163 impbid ⊢ ( 𝑦 = ∅ → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
165 neeq1 ⊢ ( 𝑦 = suc 𝑧 → ( 𝑦 ≠ ∅ ↔ suc 𝑧 ≠ ∅ ) )
166 142 165 mpbiri ⊢ ( 𝑦 = suc 𝑧 → 𝑦 ≠ ∅ )
167 166 neneqd ⊢ ( 𝑦 = suc 𝑧 → ¬ 𝑦 = ∅ )
168 167 intnanrd ⊢ ( 𝑦 = suc 𝑧 → ¬ ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) )
169 168 rexlimivw ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ¬ ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) )
170 orel1 ⊢ ( ¬ ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
171 169 170 syl ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
172 nlimsucg ⊢ ( 𝑧 ∈ V → ¬ Lim suc 𝑧 )
173 172 elv ⊢ ¬ Lim suc 𝑧
174 limeq ⊢ ( 𝑦 = suc 𝑧 → ( Lim 𝑦 ↔ Lim suc 𝑧 ) )
175 173 174 mtbiri ⊢ ( 𝑦 = suc 𝑧 → ¬ Lim 𝑦 )
176 175 rexlimivw ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ¬ Lim 𝑦 )
177 176 intnanrd ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ¬ ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) )
178 orel1 ⊢ ( ¬ ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) → ( ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) )
179 177 178 syl ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) )
180 142 neii ⊢ ¬ suc 𝑧 = ∅
181 180 iffalsei ⊢ if ( suc 𝑧 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim suc 𝑧 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) ) ) = if ( Lim suc 𝑧 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) )
182 iffalse ⊢ ( ¬ Lim suc 𝑧 → if ( Lim suc 𝑧 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) ) = ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) )
183 71 172 182 mp2b ⊢ if ( Lim suc 𝑧 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) ) = ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) )
184 181 183 eqtri ⊢ if ( suc 𝑧 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim suc 𝑧 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) ) ) = ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) )
185 eqeq1 ⊢ ( 𝑦 = suc 𝑧 → ( 𝑦 = ∅ ↔ suc 𝑧 = ∅ ) )
186 unieq ⊢ ( 𝑦 = suc 𝑧 → ∪ 𝑦 = ∪ suc 𝑧 )
187 186 fveq2d ⊢ ( 𝑦 = suc 𝑧 → ( 𝑓 ‘ ∪ 𝑦 ) = ( 𝑓 ‘ ∪ suc 𝑧 ) )
188 187 fveq2d ⊢ ( 𝑦 = suc 𝑧 → ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) = ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) )
189 174 188 ifbieq2d ⊢ ( 𝑦 = suc 𝑧 → if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) = if ( Lim suc 𝑧 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) ) )
190 185 189 ifbieq2d ⊢ ( 𝑦 = suc 𝑧 → if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) = if ( suc 𝑧 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim suc 𝑧 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ suc 𝑧 ) ) ) ) )
191 184 190 188 3eqtr4a ⊢ ( 𝑦 = suc 𝑧 → if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) )
192 191 rexlimivw ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) )
193 192 eqeq2d ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ↔ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) )
194 193 biimprd ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
195 194 adantld ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
196 171 179 195 3syld ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
197 rexex ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ∃ 𝑧 𝑦 = suc 𝑧 )
198 193 biimpd ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) )
199 olc ⊢ ( ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) → ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) )
200 199 olcd ⊢ ( ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) → ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
201 197 198 200 syl6an ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
202 196 201 impbid ⊢ ( ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
203 140 con2i ⊢ ( Lim 𝑦 → ¬ 𝑦 = ∅ )
204 203 intnanrd ⊢ ( Lim 𝑦 → ¬ ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) )
205 204 170 syl ⊢ ( Lim 𝑦 → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
206 175 exlimiv ⊢ ( ∃ 𝑧 𝑦 = suc 𝑧 → ¬ Lim 𝑦 )
207 206 con2i ⊢ ( Lim 𝑦 → ¬ ∃ 𝑧 𝑦 = suc 𝑧 )
208 207 intnanrd ⊢ ( Lim 𝑦 → ¬ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) )
209 orel2 ⊢ ( ¬ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) → ( ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ) )
210 208 209 syl ⊢ ( Lim 𝑦 → ( ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ) )
211 203 iffalsed ⊢ ( Lim 𝑦 → if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) = if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) )
212 iftrue ⊢ ( Lim 𝑦 → if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) = ∪ ( 𝑓 “ 𝑦 ) )
213 211 212 eqtrd ⊢ ( Lim 𝑦 → if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) = ∪ ( 𝑓 “ 𝑦 ) )
214 213 eqeq2d ⊢ ( Lim 𝑦 → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ↔ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) )
215 214 biimprd ⊢ ( Lim 𝑦 → ( 𝑥 = ∪ ( 𝑓 “ 𝑦 ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
216 215 adantld ⊢ ( Lim 𝑦 → ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
217 205 210 216 3syld ⊢ ( Lim 𝑦 → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
218 217 adantl ⊢ ( ( 𝑦 ∈ V ∧ Lim 𝑦 ) → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) → 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
219 214 biimpd ⊢ ( Lim 𝑦 → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) )
220 219 anc2li ⊢ ( Lim 𝑦 → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ) )
221 orc ⊢ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) → ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) )
222 221 olcd ⊢ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) → ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
223 220 222 syl6 ⊢ ( Lim 𝑦 → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
224 223 adantl ⊢ ( ( 𝑦 ∈ V ∧ Lim 𝑦 ) → ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) → ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
225 218 224 impbid ⊢ ( ( 𝑦 ∈ V ∧ Lim 𝑦 ) → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
226 164 202 225 3jaoi ⊢ ( ( 𝑦 = ∅ ∨ ∃ 𝑧 ∈ On 𝑦 = suc 𝑧 ∨ ( 𝑦 ∈ V ∧ Lim 𝑦 ) ) → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
227 137 226 sylbi ⊢ ( 𝑦 ∈ On → ( ( ( 𝑦 = ∅ ∧ 𝑥 = ∪ { 𝐴 } ) ∨ ( ( Lim 𝑦 ∧ 𝑥 = ∪ ( 𝑓 “ 𝑦 ) ) ∨ ( ∃ 𝑧 𝑦 = suc 𝑧 ∧ 𝑥 = ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
228 136 227 bitrid ⊢ ( 𝑦 ∈ On → ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ↔ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
229 53 228 syl ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ↔ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
230 26 69 brcnv ⊢ ( 𝑥 ◡ Apply ⟨ 𝑓 , 𝑦 ⟩ ↔ ⟨ 𝑓 , 𝑦 ⟩ Apply 𝑥 )
231 12 39 26 brapply ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ Apply 𝑥 ↔ 𝑥 = ( 𝑓 ‘ 𝑦 ) )
232 230 231 bitri ⊢ ( 𝑥 ◡ Apply ⟨ 𝑓 , 𝑦 ⟩ ↔ 𝑥 = ( 𝑓 ‘ 𝑦 ) )
233 232 a1i ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → ( 𝑥 ◡ Apply ⟨ 𝑓 , 𝑦 ⟩ ↔ 𝑥 = ( 𝑓 ‘ 𝑦 ) ) )
234 229 233 anbi12d ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → ( ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ∧ 𝑥 ◡ Apply ⟨ 𝑓 , 𝑦 ⟩ ) ↔ ( 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ∧ 𝑥 = ( 𝑓 ‘ 𝑦 ) ) ) )
235 234 biancomd ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → ( ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ∧ 𝑥 ◡ Apply ⟨ 𝑓 , 𝑦 ⟩ ) ↔ ( 𝑥 = ( 𝑓 ‘ 𝑦 ) ∧ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
236 235 exbidv ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → ( ∃ 𝑥 ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ∧ 𝑥 ◡ Apply ⟨ 𝑓 , 𝑦 ⟩ ) ↔ ∃ 𝑥 ( 𝑥 = ( 𝑓 ‘ 𝑦 ) ∧ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
237 df-br ⊢ ( 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ↔ ⟨ 𝑓 , 𝑦 ⟩ ∈ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) )
238 69 elfix ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ∈ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ↔ ⟨ 𝑓 , 𝑦 ⟩ ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ⟨ 𝑓 , 𝑦 ⟩ )
239 69 69 brco ⊢ ( ⟨ 𝑓 , 𝑦 ⟩ ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ⟨ 𝑓 , 𝑦 ⟩ ↔ ∃ 𝑥 ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ∧ 𝑥 ◡ Apply ⟨ 𝑓 , 𝑦 ⟩ ) )
240 237 238 239 3bitri ⊢ ( 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ↔ ∃ 𝑥 ( ⟨ 𝑓 , 𝑦 ⟩ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) 𝑥 ∧ 𝑥 ◡ Apply ⟨ 𝑓 , 𝑦 ⟩ ) )
241 fvex ⊢ ( 𝑓 ‘ 𝑦 ) ∈ V
242 241 eqvinc ⊢ ( ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ↔ ∃ 𝑥 ( 𝑥 = ( 𝑓 ‘ 𝑦 ) ∧ 𝑥 = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
243 236 240 242 3bitr4g ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → ( 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ↔ ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
244 243 notbid ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ∧ 𝑦 ∈ dom 𝑓 ) → ( ¬ 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ↔ ¬ ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
245 244 3expia ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( 𝑦 ∈ dom 𝑓 → ( ¬ 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ↔ ¬ ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
246 245 pm5.32d ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( ( 𝑦 ∈ dom 𝑓 ∧ ¬ 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ) ↔ ( 𝑦 ∈ dom 𝑓 ∧ ¬ ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
247 annim ⊢ ( ( 𝑦 ∈ dom 𝑓 ∧ ¬ ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ ¬ ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
248 246 247 bitrdi ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( ( 𝑦 ∈ dom 𝑓 ∧ ¬ 𝑓 Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) 𝑦 ) ↔ ¬ ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
249 51 248 bitrid ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( 𝑓 ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) 𝑦 ↔ ¬ ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
250 249 exbidv ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( ∃ 𝑦 𝑓 ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) 𝑦 ↔ ∃ 𝑦 ¬ ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
251 exnal ⊢ ( ∃ 𝑦 ¬ ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ ¬ ∀ 𝑦 ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
252 250 251 bitr2di ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( ¬ ∀ 𝑦 ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ ∃ 𝑦 𝑓 ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) 𝑦 ) )
253 12 eldm ⊢ ( 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ↔ ∃ 𝑦 𝑓 ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) 𝑦 )
254 252 253 bitr4di ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( ¬ ∀ 𝑦 ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) )
255 254 con1bid ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( ¬ 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ↔ ∀ 𝑦 ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
256 df-ral ⊢ ( ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ↔ ∀ 𝑦 ( 𝑦 ∈ dom 𝑓 → ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
257 255 256 bitr4di ⊢ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) → ( ¬ 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ↔ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
258 257 pm5.32i ⊢ ( ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) ∧ ¬ 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) ↔ ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
259 anass ⊢ ( ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ↔ ( Fun 𝑓 ∧ ( dom 𝑓 ∈ On ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
260 258 259 bitri ⊢ ( ( ( Fun 𝑓 ∧ dom 𝑓 ∈ On ) ∧ ¬ 𝑓 ∈ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) ↔ ( Fun 𝑓 ∧ ( dom 𝑓 ∈ On ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
261 21 37 260 3bitri ⊢ ( 𝑓 ∈ ( ( Funs ∩ ( ◡ Domain “ On ) ) ∖ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) ↔ ( Fun 𝑓 ∧ ( dom 𝑓 ∈ On ∧ ∀ 𝑦 ∈ dom 𝑓 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) ) )
262 19 20 261 3bitr4ri ⊢ ( 𝑓 ∈ ( ( Funs ∩ ( ◡ Domain “ On ) ) ∖ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) ↔ ∃ 𝑥 ∈ On ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) )
263 262 eqabi ⊢ ( ( Funs ∩ ( ◡ Domain “ On ) ) ∖ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) = { 𝑓 ∣ ∃ 𝑥 ∈ On ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) }
264 263 unieqi ⊢ ∪ ( ( Funs ∩ ( ◡ Domain “ On ) ) ∖ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) ) = ∪ { 𝑓 ∣ ∃ 𝑥 ∈ On ( 𝑓 Fn 𝑥 ∧ ∀ 𝑦 ∈ 𝑥 ( 𝑓 ‘ 𝑦 ) = if ( 𝑦 = ∅ , if ( 𝐴 ∈ V , 𝐴 , ∅ ) , if ( Lim 𝑦 , ∪ ( 𝑓 “ 𝑦 ) , ( 𝐹 ‘ ( 𝑓 ‘ ∪ 𝑦 ) ) ) ) ) }
265 1 264 eqtr4i ⊢ rec ( 𝐹 , 𝐴 ) = ∪ ( ( Funs ∩ ( ◡ Domain “ On ) ) ∖ dom ( ( ◡ E ∘ Domain ) ∖ Fix ( ◡ Apply ∘ ( ( ( V × { ∅ } ) × { ∪ { 𝐴 } } ) ∪ ( ( ( Bigcup ∘ Img ) ↾ ( V × Limits ) ) ∪ ( ( FullFun 𝐹 ∘ ( Apply ∘ pprod ( I , Bigcup ) ) ) ↾ ( V × ran Succ ) ) ) ) ) ) )