Theorem tz7.44-2 8392

Description: The value of 𝐹 at a successor ordinal. Part 2 of Theorem 7.44 of [TakeutiZaring] p. 49. (Contributed by NM, 23-Apr-1995.) Remove unnecessary distinct variable conditions. (Revised by David Abernethy, 19-Jun-2012.) (Revised by Mario Carneiro, 14-Nov-2014.)

Hypotheses

Ref	Expression
tz7.44.1	⊢ 𝐺 = (𝑥 ∈ V ↦ if(𝑥 = ∅, 𝐴, if(Lim dom 𝑥, ∪ ran 𝑥, (𝐻‘(𝑥‘∪ dom 𝑥)))))
tz7.44.2	⊢ (𝑦 ∈ 𝑋 → (𝐹‘𝑦) = (𝐺‘(𝐹 ↾ 𝑦)))
tz7.44.3	⊢ (𝑦 ∈ 𝑋 → (𝐹 ↾ 𝑦) ∈ V)
tz7.44.4	⊢ 𝐹 Fn 𝑋
tz7.44.5	⊢ Ord 𝑋

Assertion

Ref	Expression
tz7.44-2	⊢ (suc 𝐵 ∈ 𝑋 → (𝐹‘suc 𝐵) = (𝐻‘(𝐹‘𝐵)))

Distinct variable groups:   𝑥,𝐴   𝑥,𝑦,𝐵   𝑥,𝐹,𝑦   𝑦,𝐺   𝑥,𝐻   𝑦,𝑋

Allowed substitution hints:   𝐴(𝑦)   𝐺(𝑥)   𝐻(𝑦)   𝑋(𝑥)

Proof of Theorem tz7.44-2

Step	Hyp	Ref	Expression
1		fveq2 6881	. . . 4 ⊢ (𝑦 = suc 𝐵 → (𝐹‘𝑦) = (𝐹‘suc 𝐵))
2		reseq2 5972	. . . . 5 ⊢ (𝑦 = suc 𝐵 → (𝐹 ↾ 𝑦) = (𝐹 ↾ suc 𝐵))
3	2	fveq2d 6885	. . . 4 ⊢ (𝑦 = suc 𝐵 → (𝐺‘(𝐹 ↾ 𝑦)) = (𝐺‘(𝐹 ↾ suc 𝐵)))
4	1, 3	eqeq12d 2778	. . 3 ⊢ (𝑦 = suc 𝐵 → ((𝐹‘𝑦) = (𝐺‘(𝐹 ↾ 𝑦)) ↔ (𝐹‘suc 𝐵) = (𝐺‘(𝐹 ↾ suc 𝐵))))
5		tz7.44.2	. . 3 ⊢ (𝑦 ∈ 𝑋 → (𝐹‘𝑦) = (𝐺‘(𝐹 ↾ 𝑦)))
6	4, 5	vtoclga 3540	. 2 ⊢ (suc 𝐵 ∈ 𝑋 → (𝐹‘suc 𝐵) = (𝐺‘(𝐹 ↾ suc 𝐵)))
7		tz7.44.1	. . 3 ⊢ 𝐺 = (𝑥 ∈ V ↦ if(𝑥 = ∅, 𝐴, if(Lim dom 𝑥, ∪ ran 𝑥, (𝐻‘(𝑥‘∪ dom 𝑥)))))
8		eqeq1 2766	. . . 4 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → (𝑥 = ∅ ↔ (𝐹 ↾ suc 𝐵) = ∅))
9		dmeq 5892	. . . . . 6 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → dom 𝑥 = dom (𝐹 ↾ suc 𝐵))
10		limeq 6372	. . . . . 6 ⊢ (dom 𝑥 = dom (𝐹 ↾ suc 𝐵) → (Lim dom 𝑥 ↔ Lim dom (𝐹 ↾ suc 𝐵)))
11	9, 10	syl 18	. . . . 5 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → (Lim dom 𝑥 ↔ Lim dom (𝐹 ↾ suc 𝐵)))
12		rneq 5925	. . . . . 6 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → ran 𝑥 = ran (𝐹 ↾ suc 𝐵))
13	12	unieqd 4884	. . . . 5 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → ∪ ran 𝑥 = ∪ ran (𝐹 ↾ suc 𝐵))
14		fveq1 6880	. . . . . . 7 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → (𝑥‘∪ dom 𝑥) = ((𝐹 ↾ suc 𝐵)‘∪ dom 𝑥))
15	9	unieqd 4884	. . . . . . . 8 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → ∪ dom 𝑥 = ∪ dom (𝐹 ↾ suc 𝐵))
16	15	fveq2d 6885	. . . . . . 7 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → ((𝐹 ↾ suc 𝐵)‘∪ dom 𝑥) = ((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵)))
17	14, 16	eqtrd 2797	. . . . . 6 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → (𝑥‘∪ dom 𝑥) = ((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵)))
18	17	fveq2d 6885	. . . . 5 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → (𝐻‘(𝑥‘∪ dom 𝑥)) = (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵))))
19	11, 13, 18	ifbieq12d 4515	. . . 4 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → if(Lim dom 𝑥, ∪ ran 𝑥, (𝐻‘(𝑥‘∪ dom 𝑥))) = if(Lim dom (𝐹 ↾ suc 𝐵), ∪ ran (𝐹 ↾ suc 𝐵), (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵)))))
20	8, 19	ifbieq2d 4513	. . 3 ⊢ (𝑥 = (𝐹 ↾ suc 𝐵) → if(𝑥 = ∅, 𝐴, if(Lim dom 𝑥, ∪ ran 𝑥, (𝐻‘(𝑥‘∪ dom 𝑥)))) = if((𝐹 ↾ suc 𝐵) = ∅, 𝐴, if(Lim dom (𝐹 ↾ suc 𝐵), ∪ ran (𝐹 ↾ suc 𝐵), (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵))))))
21	2	eleq1d 2847	. . . 4 ⊢ (𝑦 = suc 𝐵 → ((𝐹 ↾ 𝑦) ∈ V ↔ (𝐹 ↾ suc 𝐵) ∈ V))
22		tz7.44.3	. . . 4 ⊢ (𝑦 ∈ 𝑋 → (𝐹 ↾ 𝑦) ∈ V)
23	21, 22	vtoclga 3540	. . 3 ⊢ (suc 𝐵 ∈ 𝑋 → (𝐹 ↾ suc 𝐵) ∈ V)
24		noel 4290	. . . . . . 7 ⊢ ¬ 𝐵 ∈ ∅
25		dmeq 5892	. . . . . . . . 9 ⊢ ((𝐹 ↾ suc 𝐵) = ∅ → dom (𝐹 ↾ suc 𝐵) = dom ∅)
26		dm0 5909	. . . . . . . . 9 ⊢ dom ∅ = ∅
27	25, 26	eqtrdi 2813	. . . . . . . 8 ⊢ ((𝐹 ↾ suc 𝐵) = ∅ → dom (𝐹 ↾ suc 𝐵) = ∅)
28		tz7.44.5	. . . . . . . . . . . . 13 ⊢ Ord 𝑋
29		ordsson 7780	. . . . . . . . . . . . 13 ⊢ (Ord 𝑋 → 𝑋 ⊆ On)
30	28, 29	ax-mp 5	. . . . . . . . . . . 12 ⊢ 𝑋 ⊆ On
31		ordtr 6374	. . . . . . . . . . . . . 14 ⊢ (Ord 𝑋 → Tr 𝑋)
32	28, 31	ax-mp 5	. . . . . . . . . . . . 13 ⊢ Tr 𝑋
33		trsuc 6450	. . . . . . . . . . . . 13 ⊢ ((Tr 𝑋 ∧ suc 𝐵 ∈ 𝑋) → 𝐵 ∈ 𝑋)
34	32, 33	mpan 702	. . . . . . . . . . . 12 ⊢ (suc 𝐵 ∈ 𝑋 → 𝐵 ∈ 𝑋)
35	30, 34	sselid 3934	. . . . . . . . . . 11 ⊢ (suc 𝐵 ∈ 𝑋 → 𝐵 ∈ On)
36		sucidg 6444	. . . . . . . . . . 11 ⊢ (𝐵 ∈ On → 𝐵 ∈ suc 𝐵)
37	35, 36	syl 18	. . . . . . . . . 10 ⊢ (suc 𝐵 ∈ 𝑋 → 𝐵 ∈ suc 𝐵)
38		dmres 6010	. . . . . . . . . . 11 ⊢ dom (𝐹 ↾ suc 𝐵) = (suc 𝐵 ∩ dom 𝐹)
39		ordelss 6376	. . . . . . . . . . . . . 14 ⊢ ((Ord 𝑋 ∧ suc 𝐵 ∈ 𝑋) → suc 𝐵 ⊆ 𝑋)
40	28, 39	mpan 702	. . . . . . . . . . . . 13 ⊢ (suc 𝐵 ∈ 𝑋 → suc 𝐵 ⊆ 𝑋)
41		tz7.44.4	. . . . . . . . . . . . . 14 ⊢ 𝐹 Fn 𝑋
42	41	fndmi 6639	. . . . . . . . . . . . 13 ⊢ dom 𝐹 = 𝑋
43	40, 42	sseqtrrdi 3977	. . . . . . . . . . . 12 ⊢ (suc 𝐵 ∈ 𝑋 → suc 𝐵 ⊆ dom 𝐹)
44		dfss2 3922	. . . . . . . . . . . 12 ⊢ (suc 𝐵 ⊆ dom 𝐹 ↔ (suc 𝐵 ∩ dom 𝐹) = suc 𝐵)
45	43, 44	sylib 221	. . . . . . . . . . 11 ⊢ (suc 𝐵 ∈ 𝑋 → (suc 𝐵 ∩ dom 𝐹) = suc 𝐵)
46	38, 45	eqtrid 2809	. . . . . . . . . 10 ⊢ (suc 𝐵 ∈ 𝑋 → dom (𝐹 ↾ suc 𝐵) = suc 𝐵)
47	37, 46	eleqtrrd 2865	. . . . . . . . 9 ⊢ (suc 𝐵 ∈ 𝑋 → 𝐵 ∈ dom (𝐹 ↾ suc 𝐵))
48		eleq2 2851	. . . . . . . . 9 ⊢ (dom (𝐹 ↾ suc 𝐵) = ∅ → (𝐵 ∈ dom (𝐹 ↾ suc 𝐵) ↔ 𝐵 ∈ ∅))
49	47, 48	syl5ibcom 248	. . . . . . . 8 ⊢ (suc 𝐵 ∈ 𝑋 → (dom (𝐹 ↾ suc 𝐵) = ∅ → 𝐵 ∈ ∅))
50	27, 49	syl5 35	. . . . . . 7 ⊢ (suc 𝐵 ∈ 𝑋 → ((𝐹 ↾ suc 𝐵) = ∅ → 𝐵 ∈ ∅))
51	24, 50	mtoi 202	. . . . . 6 ⊢ (suc 𝐵 ∈ 𝑋 → ¬ (𝐹 ↾ suc 𝐵) = ∅)
52	51	iffalsed 4497	. . . . 5 ⊢ (suc 𝐵 ∈ 𝑋 → if((𝐹 ↾ suc 𝐵) = ∅, 𝐴, if(Lim dom (𝐹 ↾ suc 𝐵), ∪ ran (𝐹 ↾ suc 𝐵), (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵))))) = if(Lim dom (𝐹 ↾ suc 𝐵), ∪ ran (𝐹 ↾ suc 𝐵), (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵)))))
53		nlimsucg 7836	. . . . . . . 8 ⊢ (𝐵 ∈ On → ¬ Lim suc 𝐵)
54	35, 53	syl 18	. . . . . . 7 ⊢ (suc 𝐵 ∈ 𝑋 → ¬ Lim suc 𝐵)
55		limeq 6372	. . . . . . . 8 ⊢ (dom (𝐹 ↾ suc 𝐵) = suc 𝐵 → (Lim dom (𝐹 ↾ suc 𝐵) ↔ Lim suc 𝐵))
56	46, 55	syl 18	. . . . . . 7 ⊢ (suc 𝐵 ∈ 𝑋 → (Lim dom (𝐹 ↾ suc 𝐵) ↔ Lim suc 𝐵))
57	54, 56	mtbird 328	. . . . . 6 ⊢ (suc 𝐵 ∈ 𝑋 → ¬ Lim dom (𝐹 ↾ suc 𝐵))
58	57	iffalsed 4497	. . . . 5 ⊢ (suc 𝐵 ∈ 𝑋 → if(Lim dom (𝐹 ↾ suc 𝐵), ∪ ran (𝐹 ↾ suc 𝐵), (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵)))) = (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵))))
59	46	unieqd 4884	. . . . . . . . 9 ⊢ (suc 𝐵 ∈ 𝑋 → ∪ dom (𝐹 ↾ suc 𝐵) = ∪ suc 𝐵)
60		eloni 6370	. . . . . . . . . 10 ⊢ (𝐵 ∈ On → Ord 𝐵)
61		ordunisuc 7826	. . . . . . . . . 10 ⊢ (Ord 𝐵 → ∪ suc 𝐵 = 𝐵)
62	35, 60, 61	3syl 19	. . . . . . . . 9 ⊢ (suc 𝐵 ∈ 𝑋 → ∪ suc 𝐵 = 𝐵)
63	59, 62	eqtrd 2797	. . . . . . . 8 ⊢ (suc 𝐵 ∈ 𝑋 → ∪ dom (𝐹 ↾ suc 𝐵) = 𝐵)
64	63	fveq2d 6885	. . . . . . 7 ⊢ (suc 𝐵 ∈ 𝑋 → ((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵)) = ((𝐹 ↾ suc 𝐵)‘𝐵))
65	37	fvresd 6901	. . . . . . 7 ⊢ (suc 𝐵 ∈ 𝑋 → ((𝐹 ↾ suc 𝐵)‘𝐵) = (𝐹‘𝐵))
66	64, 65	eqtrd 2797	. . . . . 6 ⊢ (suc 𝐵 ∈ 𝑋 → ((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵)) = (𝐹‘𝐵))
67	66	fveq2d 6885	. . . . 5 ⊢ (suc 𝐵 ∈ 𝑋 → (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵))) = (𝐻‘(𝐹‘𝐵)))
68	52, 58, 67	3eqtrd 2801	. . . 4 ⊢ (suc 𝐵 ∈ 𝑋 → if((𝐹 ↾ suc 𝐵) = ∅, 𝐴, if(Lim dom (𝐹 ↾ suc 𝐵), ∪ ran (𝐹 ↾ suc 𝐵), (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵))))) = (𝐻‘(𝐹‘𝐵)))
69		fvex 6894	. . . 4 ⊢ (𝐻‘(𝐹‘𝐵)) ∈ V
70	68, 69	eqeltrdi 2870	. . 3 ⊢ (suc 𝐵 ∈ 𝑋 → if((𝐹 ↾ suc 𝐵) = ∅, 𝐴, if(Lim dom (𝐹 ↾ suc 𝐵), ∪ ran (𝐹 ↾ suc 𝐵), (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵))))) ∈ V)
71	7, 20, 23, 70	fvmptd3 7013	. 2 ⊢ (suc 𝐵 ∈ 𝑋 → (𝐺‘(𝐹 ↾ suc 𝐵)) = if((𝐹 ↾ suc 𝐵) = ∅, 𝐴, if(Lim dom (𝐹 ↾ suc 𝐵), ∪ ran (𝐹 ↾ suc 𝐵), (𝐻‘((𝐹 ↾ suc 𝐵)‘∪ dom (𝐹 ↾ suc 𝐵))))))
72	6, 71, 68	3eqtrd 2801	1 ⊢ (suc 𝐵 ∈ 𝑋 → (𝐹‘suc 𝐵) = (𝐻‘(𝐹‘𝐵)))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   = wceq 1569   ∈ wcel 2142  Vcvv 3454   ∩ cin 3903   ⊆ wss 3904  ∅c0 4285  ifcif 4486  ∪ cuni 4871   ↦ cmpt 5191  Tr wtr 5217  dom cdm 5660  ran crn 5661   ↾ cres 5662  Ord word 6359  Oncon0 6360  Lim wlim 6361  suc csuc 6362   Fn wfn 6531  ‘cfv 6536

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-8 2144  ax-9 2152  ax-10 2175  ax-11 2191  ax-12 2212  ax-ext 2734  ax-sep 5256  ax-nul 5268  ax-pr 5403  ax-un 7734

This proof depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3or 1103  df-3an 1104  df-tru 1572  df-fal 1582  df-ex 1809  df-nf 1813  df-sb 2096  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3079  df-rex 3089  df-rab 3416  df-v 3456  df-dif 3907  df-un 3909  df-in 3911  df-ss 3921  df-pss 3924  df-nul 4286  df-if 4487  df-pw 4563  df-sn 4589  df-pr 4591  df-op 4595  df-uni 4872  df-br 5109  df-opab 5173  df-mpt 5192  df-tr 5218  df-id 5555  df-eprel 5560  df-po 5568  df-so 5569  df-fr 5613  df-we 5615  df-xp 5666  df-rel 5667  df-cnv 5668  df-co 5669  df-dm 5670  df-rn 5671  df-res 5672  df-ord 6363  df-on 6364  df-lim 6365  df-suc 6366  df-iota 6492  df-fun 6538  df-fn 6539  df-fv 6544

This theorem is used by:  rdgsucg  8408