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Theorem abianfplem 3946
Description: Lemma for abianfp 3947. We prove by transfinite induction that if F has a fixed point x, then its iterates also equal x. This lemma is used for the "trivial" direction of the main theorem.
Hypotheses
Ref Expression
abianfp.1 |- A e. V
abianfp.2 |- G = rec({<.z, w>. | w = (F` z)}, x)
Assertion
Ref Expression
abianfplem |- (v e. On -> ((F` x) = x -> (G` v) = x))
Distinct variable groups:   x,v,A   x,z,w,F,v   v,G

Proof of Theorem abianfplem
StepHypRef Expression
1 fveq2 3709 . . 3 |- (v = (/) -> (G` v) = (G` (/)))
21eqeq1d 1475 . 2 |- (v = (/) -> ((G` v) = x <-> (G` (/)) = x))
3 fveq2 3709 . . 3 |- (v = y -> (G` v) = (G` y))
43eqeq1d 1475 . 2 |- (v = y -> ((G` v) = x <-> (G` y) = x))
5 fveq2 3709 . . 3 |- (v = suc y -> (G` v) = (G` suc y))
65eqeq1d 1475 . 2 |- (v = suc y -> ((G` v) = x <-> (G` suc y) = x))
7 abianfp.2 . . . . 5 |- G = rec({<.z, w>. | w = (F` z)}, x)
87fveq1i 3710 . . . 4 |- (G` (/)) = (rec({<.z, w>. | w = (F` z)}, x)` (/))
9 visset 1804 . . . . 5 |- x e. V
109rdg0 3926 . . . 4 |- (rec({<.z, w>. | w = (F` z)}, x)` (/)) = x
118, 10eqtr 1487 . . 3 |- (G` (/)) = x
1211a1i 8 . 2 |- ((F` x) = x -> (G` (/)) = x)
13 fvex 3717 . . . . 5 |- (F` (G` y)) e. V
14 ax-17 968 . . . . . 6 |- (u e. x -> A.z u e. x)
15 ax-17 968 . . . . . 6 |- (u e. y -> A.z u e. y)
16 ax-17 968 . . . . . . 7 |- (u e. F -> A.z u e. F)
17 hbopab1 2802 . . . . . . . . . 10 |- (u e. {<.z, w>. | w = (F` z)} -> A.z u e. {<.z, w>. | w = (F` z)})
1817, 14hbrdg 3921 . . . . . . . . 9 |- (u e. rec({<.z, w>. | w = (F` z)}, x) -> A.z u e. rec({<.z, w>. | w = (F` z)}, x))
197, 18hbxfr 1555 . . . . . . . 8 |- (u e. G -> A.z u e. G)
2019, 15hbfv 3714 . . . . . . 7 |- (u e. (G` y) -> A.z u e. (G` y))
2116, 20hbfv 3714 . . . . . 6 |- (u e. (F` (G` y)) -> A.z u e. (F` (G` y)))
22 fveq2 3709 . . . . . 6 |- (z = (G` y) -> (F` z) = (F` (G` y)))
2314, 15, 21, 7, 22rdgsucopab 3931 . . . . 5 |- ((y e. On /\ (F` (G` y)) e. V) -> (G` suc y) = (F` (G` y)))
2413, 23mpan2 694 . . . 4 |- (y e. On -> (G` suc y) = (F` (G` y)))
25 fveq2 3709 . . . . 5 |- ((G` y) = x -> (F` (G` y)) = (F` x))
26 id 59 . . . . 5 |- ((F` x) = x -> (F` x) = x)
2725, 26sylan9eqr 1521 . . . 4 |- (((F` x) = x /\ (G` y) = x) -> (F` (G` y)) = x)
2824, 27sylan9eq 1519 . . 3 |- ((y e. On /\ ((F` x) = x /\ (G` y) = x)) -> (G` suc y) = x)
2928exp32 377 . 2 |- (y e. On -> ((F` x) = x -> ((G` y) = x -> (G` suc y) = x)))
30 visset 1804 . . . . . . . 8 |- v e. V
31 rdglim2a 3935 . . . . . . . 8 |- ((v e. V /\ Lim v) -> (rec({<.z, w>. | w = (F` z)}, x)` v) = U_y e. v (rec({<.z, w>. | w = (F` z)}, x)` y))
3230, 31mpan 693 . . . . . . 7 |- (Lim v -> (rec({<.z, w>. | w = (F` z)}, x)` v) = U_y e. v (rec({<.z, w>. | w = (F` z)}, x)` y))
337fveq1i 3710 . . . . . . 7 |- (G` v) = (rec({<.z, w>. | w = (F` z)}, x)` v)
347fveq1i 3710 . . . . . . . . 9 |- (G` y) = (rec({<.z, w>. | w = (F` z)}, x)` y)
3534a1i 8 . . . . . . . 8 |- (y e. v -> (G` y) = (rec({<.z, w>. | w = (F` z)}, x)` y))
3635iuneq2i 2570 . . . . . . 7 |- U_y e. v (G` y) = U_y e. v (rec({<.z, w>. | w = (F` z)}, x)` y)
3732, 33, 363eqtr4g 1523 . . . . . 6 |- (Lim v -> (G` v) = U_y e. v (G` y))
3837adantr 389 . . . . 5 |- ((Lim v /\ A.y e. v (G` y) = x) -> (G` v) = U_y e. v (G` y))
39 iuneq2 2568 . . . . . 6 |- (A.y e. v (G` y) = x -> U_y e. v (G` y) = U_y e. v x)
40 df-lim 2943 . . . . . . . 8 |- (Lim v <-> (Ord v /\ v =/= (/) /\ v = U.v))
41 3simp2 787 . . . . . . . 8 |- ((Ord v /\ v =/= (/) /\ v = U.v) -> v =/= (/))
4240, 41sylbi 199 . . . . . . 7 |- (Lim v -> v =/= (/))
43 iunconst 2562 . . . . . . 7 |- (v =/= (/) -> U_y e. v x = x)
4442, 43syl 10 . . . . . 6 |- (Lim v -> U_y e. v x = x)
4539, 44sylan9eqr 1521 . . . . 5 |- ((Lim v /\ A.y e. v (G` y) = x) -> U_y e. v (G` y) = x)
4638, 45eqtrd 1499 . . . 4 |- ((Lim v /\ A.y e. v (G` y) = x) -> (G` v) = x)
4746ex 373 . . 3 |- (Lim v -> (A.y e. v (G` y) = x -> (G` v) = x))
4847a1d 12 . 2 |- (Lim v -> ((F` x) = x -> (A.y e. v (G` y) = x -> (G` v) = x)))
492, 4, 6, 12, 29, 48tfinds2 3155 1 |- (v e. On -> ((F` x) = x -> (G` v) = x))
Colors of variables: wff set class
Syntax hints:   -> wi 3   /\ wa 223   /\ w3a 773   = wceq 953   e. wcel 955   =/= wne 1577  A.wral 1637  Vcvv 1802  (/)c0 2270  U.cuni 2493  U_ciun 2556  {copab 2656  Ord word 2937  Oncon0 2938  Lim wlim 2939  suc csuc 2940  ` cfv 3172  reccrdg 3916
This theorem is referenced by:  abianfp 3947
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 959  ax-gen 960  ax-8 961  ax-9 962  ax-10 963  ax-11 964  ax-12 965  ax-13 966  ax-14 967  ax-17 968  ax-4 970  ax-5o 972  ax-6o 975  ax-9o 1119  ax-10o 1136  ax-16 1206  ax-11o 1213  ax-ext 1452  ax-rep 2683  ax-sep 2693  ax-nul 2700  ax-pow 2732  ax-pr 2769  ax-un 2857
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3or 774  df-3an 775  df-ex 978  df-sb 1168  df-eu 1375  df-mo 1376  df-clab 1457  df-cleq 1462  df-clel 1465  df-ne 1579  df-ral 1641  df-rex 1642  df-rab 1644  df-v 1803  df-sbc 1932  df-dif 2039  df-un 2040  df-in 2041  df-ss 2043  df-nul 2271  df-if 2352  df-pw 2392  df-sn 2402  df-pr 2403  df-tp 2405  df-op 2406  df-uni 2494  df-iun 2558  df-br 2610  df-opab 2657  df-tr 2671  df-eprel 2821  df-id 2824  df-po 2831  df-so 2841  df-fr 2907  df-we 2924  df-ord 2941  df-on 2942  df-lim 2943  df-suc 2944  df-xp 3174  df-rel 3175  df-cnv 3176  df-co 3177  df-dm 3178  df-rn 3179  df-res 3180  df-ima 3181  df-fun 3182  df-fn 3183  df-fv 3188  df-rdg 3917
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