Theorem frr2 9449

Description: Law of general well-founded recursion, part two. Now we establish the value of 𝐹 within 𝐴. (Contributed by Scott Fenton, 11-Sep-2023.)

Hypothesis

Ref	Expression
frr.1	⊢ 𝐹 = frecs(𝑅, 𝐴, 𝐺)

Assertion

Ref	Expression
frr2	⊢ (((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) ∧ 𝑋 ∈ 𝐴) → (𝐹‘𝑋) = (𝑋𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑋))))

Proof of Theorem frr2

Dummy variables 𝑥 𝑦 𝑢 𝑣 𝑎 𝑏 𝑐 𝑓 𝑔 ℎ are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		frr.1	. . . . . 6 ⊢ 𝐹 = frecs(𝑅, 𝐴, 𝐺)
2	1	frr1 9448	. . . . 5 ⊢ ((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) → 𝐹 Fn 𝐴)
3	2	fndmd 6522	. . . 4 ⊢ ((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) → dom 𝐹 = 𝐴)
4	3	eleq2d 2824	. . 3 ⊢ ((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) → (𝑋 ∈ dom 𝐹 ↔ 𝑋 ∈ 𝐴))
5	4	pm5.32i 574	. 2 ⊢ (((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) ∧ 𝑋 ∈ dom 𝐹) ↔ ((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) ∧ 𝑋 ∈ 𝐴))
6		fveq2 6756	. . . . . 6 ⊢ (𝑦 = 𝑋 → (𝐹‘𝑦) = (𝐹‘𝑋))
7		id 22	. . . . . . 7 ⊢ (𝑦 = 𝑋 → 𝑦 = 𝑋)
8		predeq3 6195	. . . . . . . 8 ⊢ (𝑦 = 𝑋 → Pred(𝑅, 𝐴, 𝑦) = Pred(𝑅, 𝐴, 𝑋))
9	8	reseq2d 5880	. . . . . . 7 ⊢ (𝑦 = 𝑋 → (𝐹 ↾ Pred(𝑅, 𝐴, 𝑦)) = (𝐹 ↾ Pred(𝑅, 𝐴, 𝑋)))
10	7, 9	oveq12d 7273	. . . . . 6 ⊢ (𝑦 = 𝑋 → (𝑦𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑦))) = (𝑋𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑋))))
11	6, 10	eqeq12d 2754	. . . . 5 ⊢ (𝑦 = 𝑋 → ((𝐹‘𝑦) = (𝑦𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑦))) ↔ (𝐹‘𝑋) = (𝑋𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑋)))))
12	11	imbi2d 340	. . . 4 ⊢ (𝑦 = 𝑋 → (((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) → (𝐹‘𝑦) = (𝑦𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑦)))) ↔ ((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) → (𝐹‘𝑋) = (𝑋𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑋))))))
13		eqid 2738	. . . . . . 7 ⊢ {𝑎 ∣ ∃𝑏(𝑎 Fn 𝑏 ∧ (𝑏 ⊆ 𝐴 ∧ ∀𝑐 ∈ 𝑏 Pred(𝑅, 𝐴, 𝑐) ⊆ 𝑏) ∧ ∀𝑐 ∈ 𝑏 (𝑎‘𝑐) = (𝑐𝐺(𝑎 ↾ Pred(𝑅, 𝐴, 𝑐))))} = {𝑎 ∣ ∃𝑏(𝑎 Fn 𝑏 ∧ (𝑏 ⊆ 𝐴 ∧ ∀𝑐 ∈ 𝑏 Pred(𝑅, 𝐴, 𝑐) ⊆ 𝑏) ∧ ∀𝑐 ∈ 𝑏 (𝑎‘𝑐) = (𝑐𝐺(𝑎 ↾ Pred(𝑅, 𝐴, 𝑐))))}
14	13	frrlem1 8073	. . . . . 6 ⊢ {𝑎 ∣ ∃𝑏(𝑎 Fn 𝑏 ∧ (𝑏 ⊆ 𝐴 ∧ ∀𝑐 ∈ 𝑏 Pred(𝑅, 𝐴, 𝑐) ⊆ 𝑏) ∧ ∀𝑐 ∈ 𝑏 (𝑎‘𝑐) = (𝑐𝐺(𝑎 ↾ Pred(𝑅, 𝐴, 𝑐))))} = {𝑓 ∣ ∃𝑥(𝑓 Fn 𝑥 ∧ (𝑥 ⊆ 𝐴 ∧ ∀𝑦 ∈ 𝑥 Pred(𝑅, 𝐴, 𝑦) ⊆ 𝑥) ∧ ∀𝑦 ∈ 𝑥 (𝑓‘𝑦) = (𝑦𝐺(𝑓 ↾ Pred(𝑅, 𝐴, 𝑦))))}
15	14, 1	frrlem15 9446	. . . . . 6 ⊢ (((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) ∧ (𝑔 ∈ {𝑎 ∣ ∃𝑏(𝑎 Fn 𝑏 ∧ (𝑏 ⊆ 𝐴 ∧ ∀𝑐 ∈ 𝑏 Pred(𝑅, 𝐴, 𝑐) ⊆ 𝑏) ∧ ∀𝑐 ∈ 𝑏 (𝑎‘𝑐) = (𝑐𝐺(𝑎 ↾ Pred(𝑅, 𝐴, 𝑐))))} ∧ ℎ ∈ {𝑎 ∣ ∃𝑏(𝑎 Fn 𝑏 ∧ (𝑏 ⊆ 𝐴 ∧ ∀𝑐 ∈ 𝑏 Pred(𝑅, 𝐴, 𝑐) ⊆ 𝑏) ∧ ∀𝑐 ∈ 𝑏 (𝑎‘𝑐) = (𝑐𝐺(𝑎 ↾ Pred(𝑅, 𝐴, 𝑐))))})) → ((𝑥𝑔𝑢 ∧ 𝑥ℎ𝑣) → 𝑢 = 𝑣))
16	14, 1, 15	frrlem10 8082	. . . . 5 ⊢ (((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) ∧ 𝑦 ∈ dom 𝐹) → (𝐹‘𝑦) = (𝑦𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑦))))
17	16	expcom 413	. . . 4 ⊢ (𝑦 ∈ dom 𝐹 → ((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) → (𝐹‘𝑦) = (𝑦𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑦)))))
18	12, 17	vtoclga 3503	. . 3 ⊢ (𝑋 ∈ dom 𝐹 → ((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) → (𝐹‘𝑋) = (𝑋𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑋)))))
19	18	impcom 407	. 2 ⊢ (((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) ∧ 𝑋 ∈ dom 𝐹) → (𝐹‘𝑋) = (𝑋𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑋))))
20	5, 19	sylbir 234	1 ⊢ (((𝑅 Fr 𝐴 ∧ 𝑅 Se 𝐴) ∧ 𝑋 ∈ 𝐴) → (𝐹‘𝑋) = (𝑋𝐺(𝐹 ↾ Pred(𝑅, 𝐴, 𝑋))))

Syntax hints:   → wi 4   ∧ wa 395   ∧ w3a 1085   = wceq 1539  ∃wex 1783   ∈ wcel 2108  {cab 2715  ∀wral 3063   ⊆ wss 3883   Fr wfr 5532   Se wse 5533  dom cdm 5580   ↾ cres 5582  Predcpred 6190   Fn wfn 6413  ‘cfv 6418  (class class class)co 7255  frecscfrecs 8067

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1799  ax-4 1813  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2110  ax-9 2118  ax-10 2139  ax-11 2156  ax-12 2173  ax-ext 2709  ax-rep 5205  ax-sep 5218  ax-nul 5225  ax-pr 5347  ax-un 7566  ax-inf2 9329

This theorem depends on definitions:  df-bi 206  df-an 396  df-or 844  df-3or 1086  df-3an 1087  df-tru 1542  df-fal 1552  df-ex 1784  df-nf 1788  df-sb 2069  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2817  df-nfc 2888  df-ne 2943  df-ral 3068  df-rex 3069  df-reu 3070  df-rab 3072  df-v 3424  df-sbc 3712  df-csb 3829  df-dif 3886  df-un 3888  df-in 3890  df-ss 3900  df-pss 3902  df-nul 4254  df-if 4457  df-pw 4532  df-sn 4559  df-pr 4561  df-tp 4563  df-op 4565  df-uni 4837  df-iun 4923  df-br 5071  df-opab 5133  df-mpt 5154  df-tr 5188  df-id 5480  df-eprel 5486  df-po 5494  df-so 5495  df-fr 5535  df-se 5536  df-we 5537  df-xp 5586  df-rel 5587  df-cnv 5588  df-co 5589  df-dm 5590  df-rn 5591  df-res 5592  df-ima 5593  df-pred 6191  df-ord 6254  df-on 6255  df-lim 6256  df-suc 6257  df-iota 6376  df-fun 6420  df-fn 6421  df-f 6422  df-f1 6423  df-fo 6424  df-f1o 6425  df-fv 6426  df-ov 7258  df-om 7688  df-2nd 7805  df-frecs 8068  df-wrecs 8099  df-recs 8173  df-rdg 8212  df-trpred 9396

This theorem is referenced by:  frr3  9450