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Theorem frrlem6 8218
Description: Lemma for well-founded recursion. The well-founded recursion generator is a relation. (Contributed by Scott Fenton, 27-Aug-2022.)
Hypotheses
Ref Expression
frrlem5.1 𝐵 = {𝑓 ∣ ∃𝑥(𝑓 Fn 𝑥 ∧ (𝑥𝐴 ∧ ∀𝑦𝑥 Pred(𝑅, 𝐴, 𝑦) ⊆ 𝑥) ∧ ∀𝑦𝑥 (𝑓𝑦) = (𝑦𝐺(𝑓 ↾ Pred(𝑅, 𝐴, 𝑦))))}
frrlem5.2 𝐹 = frecs(𝑅, 𝐴, 𝐺)
Assertion
Ref Expression
frrlem6 Rel 𝐹
Distinct variable groups:   𝐴,𝑓,𝑥,𝑦   𝑓,𝐺,𝑥,𝑦   𝑅,𝑓,𝑥,𝑦
Allowed substitution hints:   𝐵(𝑥,𝑦,𝑓)   𝐹(𝑥,𝑦,𝑓)

Proof of Theorem frrlem6
Dummy variable 𝑔 is distinct from all other variables.
StepHypRef Expression
1 frrlem5.1 . . . . 5 𝐵 = {𝑓 ∣ ∃𝑥(𝑓 Fn 𝑥 ∧ (𝑥𝐴 ∧ ∀𝑦𝑥 Pred(𝑅, 𝐴, 𝑦) ⊆ 𝑥) ∧ ∀𝑦𝑥 (𝑓𝑦) = (𝑦𝐺(𝑓 ↾ Pred(𝑅, 𝐴, 𝑦))))}
2 frrlem5.2 . . . . 5 𝐹 = frecs(𝑅, 𝐴, 𝐺)
31, 2frrlem5 8217 . . . 4 𝐹 = 𝐵
43releqi 5731 . . 3 (Rel 𝐹 ↔ Rel 𝐵)
5 reluni 5772 . . 3 (Rel 𝐵 ↔ ∀𝑔𝐵 Rel 𝑔)
64, 5bitri 274 . 2 (Rel 𝐹 ↔ ∀𝑔𝐵 Rel 𝑔)
71frrlem2 8214 . . 3 (𝑔𝐵 → Fun 𝑔)
8 funrel 6515 . . 3 (Fun 𝑔 → Rel 𝑔)
97, 8syl 17 . 2 (𝑔𝐵 → Rel 𝑔)
106, 9mprgbir 3069 1 Rel 𝐹
Colors of variables: wff setvar class
Syntax hints:  wa 396  w3a 1087   = wceq 1541  wex 1781  wcel 2106  {cab 2713  wral 3062  wss 3908   cuni 4863  cres 5633  Rel wrel 5636  Predcpred 6250  Fun wfun 6487   Fn wfn 6488  cfv 6493  (class class class)co 7353  frecscfrecs 8207
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2707
This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-3an 1089  df-tru 1544  df-fal 1554  df-ex 1782  df-nf 1786  df-sb 2068  df-clab 2714  df-cleq 2728  df-clel 2814  df-nfc 2887  df-ral 3063  df-rex 3072  df-rab 3406  df-v 3445  df-dif 3911  df-un 3913  df-in 3915  df-ss 3925  df-nul 4281  df-if 4485  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4864  df-iun 4954  df-br 5104  df-opab 5166  df-xp 5637  df-rel 5638  df-cnv 5639  df-co 5640  df-dm 5641  df-rn 5642  df-res 5643  df-ima 5644  df-pred 6251  df-iota 6445  df-fun 6495  df-fn 6496  df-fv 6501  df-ov 7356  df-frecs 8208
This theorem is referenced by:  frrlem9  8221  frrrel  8233
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