Theorem cflm 10241

Description: Value of the cofinality function at a limit ordinal. Part of Definition of cofinality of [Enderton] p. 257. (Contributed by NM, 26-Apr-2004.)

Assertion

Ref	Expression
cflm	⊢ ((𝐴 ∈ 𝐵 ∧ Lim 𝐴) → (cf‘𝐴) = ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))})

Distinct variable group:   𝑥,𝑦,𝐴

Allowed substitution hints:   𝐵(𝑥,𝑦)

Proof of Theorem cflm

Dummy variables 𝑧 𝑤 𝑣 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		elex 3493	. 2 ⊢ (𝐴 ∈ 𝐵 → 𝐴 ∈ V)
2		limsuc 7833	. . . . . . . . . . . . . . . . . 18 ⊢ (Lim 𝐴 → (𝑣 ∈ 𝐴 ↔ suc 𝑣 ∈ 𝐴))
3	2	biimpd 228	. . . . . . . . . . . . . . . . 17 ⊢ (Lim 𝐴 → (𝑣 ∈ 𝐴 → suc 𝑣 ∈ 𝐴))
4		sseq1 4006	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑧 = suc 𝑣 → (𝑧 ⊆ 𝑤 ↔ suc 𝑣 ⊆ 𝑤))
5	4	rexbidv 3179	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑧 = suc 𝑣 → (∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 ↔ ∃𝑤 ∈ 𝑦 suc 𝑣 ⊆ 𝑤))
6	5	rspcv 3608	. . . . . . . . . . . . . . . . . 18 ⊢ (suc 𝑣 ∈ 𝐴 → (∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 → ∃𝑤 ∈ 𝑦 suc 𝑣 ⊆ 𝑤))
7		sucssel 6456	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑣 ∈ V → (suc 𝑣 ⊆ 𝑤 → 𝑣 ∈ 𝑤))
8	7	elv 3481	. . . . . . . . . . . . . . . . . . . 20 ⊢ (suc 𝑣 ⊆ 𝑤 → 𝑣 ∈ 𝑤)
9	8	reximi 3085	. . . . . . . . . . . . . . . . . . 19 ⊢ (∃𝑤 ∈ 𝑦 suc 𝑣 ⊆ 𝑤 → ∃𝑤 ∈ 𝑦 𝑣 ∈ 𝑤)
10		eluni2 4911	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑣 ∈ ∪ 𝑦 ↔ ∃𝑤 ∈ 𝑦 𝑣 ∈ 𝑤)
11	9, 10	sylibr 233	. . . . . . . . . . . . . . . . . 18 ⊢ (∃𝑤 ∈ 𝑦 suc 𝑣 ⊆ 𝑤 → 𝑣 ∈ ∪ 𝑦)
12	6, 11	syl6com 37	. . . . . . . . . . . . . . . . 17 ⊢ (∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 → (suc 𝑣 ∈ 𝐴 → 𝑣 ∈ ∪ 𝑦))
13	3, 12	syl9 77	. . . . . . . . . . . . . . . 16 ⊢ (Lim 𝐴 → (∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 → (𝑣 ∈ 𝐴 → 𝑣 ∈ ∪ 𝑦)))
14	13	ralrimdv 3153	. . . . . . . . . . . . . . 15 ⊢ (Lim 𝐴 → (∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 → ∀𝑣 ∈ 𝐴 𝑣 ∈ ∪ 𝑦))
15		dfss3 3969	. . . . . . . . . . . . . . 15 ⊢ (𝐴 ⊆ ∪ 𝑦 ↔ ∀𝑣 ∈ 𝐴 𝑣 ∈ ∪ 𝑦)
16	14, 15	syl6ibr 252	. . . . . . . . . . . . . 14 ⊢ (Lim 𝐴 → (∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 → 𝐴 ⊆ ∪ 𝑦))
17	16	adantr 482	. . . . . . . . . . . . 13 ⊢ ((Lim 𝐴 ∧ 𝑦 ⊆ 𝐴) → (∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 → 𝐴 ⊆ ∪ 𝑦))
18		uniss 4915	. . . . . . . . . . . . . . 15 ⊢ (𝑦 ⊆ 𝐴 → ∪ 𝑦 ⊆ ∪ 𝐴)
19		limuni 6422	. . . . . . . . . . . . . . . 16 ⊢ (Lim 𝐴 → 𝐴 = ∪ 𝐴)
20	19	sseq2d 4013	. . . . . . . . . . . . . . 15 ⊢ (Lim 𝐴 → (∪ 𝑦 ⊆ 𝐴 ↔ ∪ 𝑦 ⊆ ∪ 𝐴))
21	18, 20	imbitrrid 245	. . . . . . . . . . . . . 14 ⊢ (Lim 𝐴 → (𝑦 ⊆ 𝐴 → ∪ 𝑦 ⊆ 𝐴))
22	21	imp 408	. . . . . . . . . . . . 13 ⊢ ((Lim 𝐴 ∧ 𝑦 ⊆ 𝐴) → ∪ 𝑦 ⊆ 𝐴)
23	17, 22	jctird 528	. . . . . . . . . . . 12 ⊢ ((Lim 𝐴 ∧ 𝑦 ⊆ 𝐴) → (∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 → (𝐴 ⊆ ∪ 𝑦 ∧ ∪ 𝑦 ⊆ 𝐴)))
24		eqss 3996	. . . . . . . . . . . 12 ⊢ (𝐴 = ∪ 𝑦 ↔ (𝐴 ⊆ ∪ 𝑦 ∧ ∪ 𝑦 ⊆ 𝐴))
25	23, 24	syl6ibr 252	. . . . . . . . . . 11 ⊢ ((Lim 𝐴 ∧ 𝑦 ⊆ 𝐴) → (∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤 → 𝐴 = ∪ 𝑦))
26	25	imdistanda 573	. . . . . . . . . 10 ⊢ (Lim 𝐴 → ((𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤) → (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦)))
27	26	anim2d 613	. . . . . . . . 9 ⊢ (Lim 𝐴 → ((𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤)) → (𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))))
28	27	eximdv 1921	. . . . . . . 8 ⊢ (Lim 𝐴 → (∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤)) → ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))))
29	28	ss2abdv 4059	. . . . . . 7 ⊢ (Lim 𝐴 → {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤))} ⊆ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))})
30		intss 4972	. . . . . . 7 ⊢ ({𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤))} ⊆ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} → ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤))})
31	29, 30	syl 17	. . . . . 6 ⊢ (Lim 𝐴 → ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤))})
32	31	adantl 483	. . . . 5 ⊢ ((𝐴 ∈ V ∧ Lim 𝐴) → ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤))})
33		limelon 6425	. . . . . 6 ⊢ ((𝐴 ∈ V ∧ Lim 𝐴) → 𝐴 ∈ On)
34		cfval 10238	. . . . . 6 ⊢ (𝐴 ∈ On → (cf‘𝐴) = ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤))})
35	33, 34	syl 17	. . . . 5 ⊢ ((𝐴 ∈ V ∧ Lim 𝐴) → (cf‘𝐴) = ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ ∀𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝑦 𝑧 ⊆ 𝑤))})
36	32, 35	sseqtrrd 4022	. . . 4 ⊢ ((𝐴 ∈ V ∧ Lim 𝐴) → ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ⊆ (cf‘𝐴))
37		cfub 10240	. . . . 5 ⊢ (cf‘𝐴) ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 ⊆ ∪ 𝑦))}
38		eqimss 4039	. . . . . . . . . 10 ⊢ (𝐴 = ∪ 𝑦 → 𝐴 ⊆ ∪ 𝑦)
39	38	anim2i 618	. . . . . . . . 9 ⊢ ((𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦) → (𝑦 ⊆ 𝐴 ∧ 𝐴 ⊆ ∪ 𝑦))
40	39	anim2i 618	. . . . . . . 8 ⊢ ((𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦)) → (𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 ⊆ ∪ 𝑦)))
41	40	eximi 1838	. . . . . . 7 ⊢ (∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦)) → ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 ⊆ ∪ 𝑦)))
42	41	ss2abi 4062	. . . . . 6 ⊢ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ⊆ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 ⊆ ∪ 𝑦))}
43		intss 4972	. . . . . 6 ⊢ ({𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ⊆ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 ⊆ ∪ 𝑦))} → ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 ⊆ ∪ 𝑦))} ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))})
44	42, 43	ax-mp 5	. . . . 5 ⊢ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 ⊆ ∪ 𝑦))} ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))}
45	37, 44	sstri 3990	. . . 4 ⊢ (cf‘𝐴) ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))}
46	36, 45	jctil 521	. . 3 ⊢ ((𝐴 ∈ V ∧ Lim 𝐴) → ((cf‘𝐴) ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ∧ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ⊆ (cf‘𝐴)))
47		eqss 3996	. . 3 ⊢ ((cf‘𝐴) = ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ↔ ((cf‘𝐴) ⊆ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ∧ ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))} ⊆ (cf‘𝐴)))
48	46, 47	sylibr 233	. 2 ⊢ ((𝐴 ∈ V ∧ Lim 𝐴) → (cf‘𝐴) = ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))})
49	1, 48	sylan 581	1 ⊢ ((𝐴 ∈ 𝐵 ∧ Lim 𝐴) → (cf‘𝐴) = ∩ {𝑥 ∣ ∃𝑦(𝑥 = (card‘𝑦) ∧ (𝑦 ⊆ 𝐴 ∧ 𝐴 = ∪ 𝑦))})

Syntax hints:   → wi 4   ∧ wa 397   = wceq 1542  ∃wex 1782   ∈ wcel 2107  {cab 2710  ∀wral 3062  ∃wrex 3071  Vcvv 3475   ⊆ wss 3947  ∪ cuni 4907  ∩ cint 4949  Oncon0 6361  Lim wlim 6362  suc csuc 6363  ‘cfv 6540  cardccrd 9926  cfccf 9928

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2109  ax-9 2117  ax-10 2138  ax-11 2155  ax-12 2172  ax-ext 2704  ax-sep 5298  ax-nul 5305  ax-pr 5426  ax-un 7720

This theorem depends on definitions:  df-bi 206  df-an 398  df-or 847  df-3or 1089  df-3an 1090  df-tru 1545  df-fal 1555  df-ex 1783  df-nf 1787  df-sb 2069  df-mo 2535  df-eu 2564  df-clab 2711  df-cleq 2725  df-clel 2811  df-nfc 2886  df-ne 2942  df-ral 3063  df-rex 3072  df-rab 3434  df-v 3477  df-dif 3950  df-un 3952  df-in 3954  df-ss 3964  df-pss 3966  df-nul 4322  df-if 4528  df-pw 4603  df-sn 4628  df-pr 4630  df-op 4634  df-uni 4908  df-int 4950  df-br 5148  df-opab 5210  df-mpt 5231  df-tr 5265  df-id 5573  df-eprel 5579  df-po 5587  df-so 5588  df-fr 5630  df-we 5632  df-xp 5681  df-rel 5682  df-cnv 5683  df-co 5684  df-dm 5685  df-rn 5686  df-res 5687  df-ima 5688  df-ord 6364  df-on 6365  df-lim 6366  df-suc 6367  df-iota 6492  df-fun 6542  df-fn 6543  df-f 6544  df-fv 6548  df-card 9930  df-cf 9932

This theorem is referenced by:  gruina  10809