Theorem r1filimi 35506

Description: If all elements in a finite set appear in the cumulative hierarchy prior to a limit ordinal, then that set also appears in the cumulative hierarchy prior to the limit ordinal. (Contributed by BTernaryTau, 19-Jan-2026.)

Assertion

Ref	Expression
r1filimi	⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → 𝐴 ∈ ∪ (𝑅1 “ 𝐵))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem r1filimi

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

Step	Hyp	Ref	Expression
1		raleq 3320	. . . . . . 7 ⊢ (𝑎 = 𝐴 → (∀𝑥 ∈ 𝑎 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ↔ ∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵)))
2		eleq1 2851	. . . . . . 7 ⊢ (𝑎 = 𝐴 → (𝑎 ∈ ∪ (𝑅1 “ On) ↔ 𝐴 ∈ ∪ (𝑅1 “ On)))
3	1, 2	imbi12d 347	. . . . . 6 ⊢ (𝑎 = 𝐴 → ((∀𝑥 ∈ 𝑎 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → 𝑎 ∈ ∪ (𝑅1 “ On)) ↔ (∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → 𝐴 ∈ ∪ (𝑅1 “ On))))
4	3	imbi2d 343	. . . . 5 ⊢ (𝑎 = 𝐴 → ((Lim 𝐵 → (∀𝑥 ∈ 𝑎 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → 𝑎 ∈ ∪ (𝑅1 “ On))) ↔ (Lim 𝐵 → (∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → 𝐴 ∈ ∪ (𝑅1 “ On)))))
5		r1funlim 9734	. . . . . . . . . 10 ⊢ (Fun 𝑅1 ∧ Lim dom 𝑅1)
6	5	simpli 488	. . . . . . . . 9 ⊢ Fun 𝑅1
7		eluniima 7248	. . . . . . . . 9 ⊢ (Fun 𝑅1 → (𝑥 ∈ ∪ (𝑅1 “ 𝐵) ↔ ∃𝑦 ∈ 𝐵 𝑥 ∈ (𝑅1‘𝑦)))
8	6, 7	ax-mp 5	. . . . . . . 8 ⊢ (𝑥 ∈ ∪ (𝑅1 “ 𝐵) ↔ ∃𝑦 ∈ 𝐵 𝑥 ∈ (𝑅1‘𝑦))
9		limord 6422	. . . . . . . . . . . 12 ⊢ (Lim 𝐵 → Ord 𝐵)
10		ordsson 7778	. . . . . . . . . . . 12 ⊢ (Ord 𝐵 → 𝐵 ⊆ On)
11	9, 10	syl 18	. . . . . . . . . . 11 ⊢ (Lim 𝐵 → 𝐵 ⊆ On)
12	11	sseld 3936	. . . . . . . . . 10 ⊢ (Lim 𝐵 → (𝑦 ∈ 𝐵 → 𝑦 ∈ On))
13	12	anim1d 622	. . . . . . . . 9 ⊢ (Lim 𝐵 → ((𝑦 ∈ 𝐵 ∧ 𝑥 ∈ (𝑅1‘𝑦)) → (𝑦 ∈ On ∧ 𝑥 ∈ (𝑅1‘𝑦))))
14	13	reximdv2 3175	. . . . . . . 8 ⊢ (Lim 𝐵 → (∃𝑦 ∈ 𝐵 𝑥 ∈ (𝑅1‘𝑦) → ∃𝑦 ∈ On 𝑥 ∈ (𝑅1‘𝑦)))
15	8, 14	biimtrid 245	. . . . . . 7 ⊢ (Lim 𝐵 → (𝑥 ∈ ∪ (𝑅1 “ 𝐵) → ∃𝑦 ∈ On 𝑥 ∈ (𝑅1‘𝑦)))
16	15	ralimdv 3179	. . . . . 6 ⊢ (Lim 𝐵 → (∀𝑥 ∈ 𝑎 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → ∀𝑥 ∈ 𝑎 ∃𝑦 ∈ On 𝑥 ∈ (𝑅1‘𝑦)))
17		vex 3459	. . . . . . . 8 ⊢ 𝑎 ∈ V
18	17	tz9.12 9758	. . . . . . 7 ⊢ (∀𝑥 ∈ 𝑎 ∃𝑦 ∈ On 𝑥 ∈ (𝑅1‘𝑦) → ∃𝑦 ∈ On 𝑎 ∈ (𝑅1‘𝑦))
19		eluniima 7248	. . . . . . . 8 ⊢ (Fun 𝑅1 → (𝑎 ∈ ∪ (𝑅1 “ On) ↔ ∃𝑦 ∈ On 𝑎 ∈ (𝑅1‘𝑦)))
20	6, 19	ax-mp 5	. . . . . . 7 ⊢ (𝑎 ∈ ∪ (𝑅1 “ On) ↔ ∃𝑦 ∈ On 𝑎 ∈ (𝑅1‘𝑦))
21	18, 20	sylibr 237	. . . . . 6 ⊢ (∀𝑥 ∈ 𝑎 ∃𝑦 ∈ On 𝑥 ∈ (𝑅1‘𝑦) → 𝑎 ∈ ∪ (𝑅1 “ On))
22	16, 21	syl6 36	. . . . 5 ⊢ (Lim 𝐵 → (∀𝑥 ∈ 𝑎 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → 𝑎 ∈ ∪ (𝑅1 “ On)))
23	4, 22	vtoclg 3522	. . . 4 ⊢ (𝐴 ∈ Fin → (Lim 𝐵 → (∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → 𝐴 ∈ ∪ (𝑅1 “ On))))
24	23	impcomd 416	. . 3 ⊢ (𝐴 ∈ Fin → ((∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → 𝐴 ∈ ∪ (𝑅1 “ On)))
25	24	3impib 1134	. 2 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → 𝐴 ∈ ∪ (𝑅1 “ On))
26		simp3 1156	. 2 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → Lim 𝐵)
27		simp1 1154	. . 3 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → 𝐴 ∈ Fin)
28		eluniima 7248	. . . . . . . . 9 ⊢ (Fun 𝑅1 → (𝑥 ∈ ∪ (𝑅1 “ 𝐵) ↔ ∃𝑧 ∈ 𝐵 𝑥 ∈ (𝑅1‘𝑧)))
29	6, 28	ax-mp 5	. . . . . . . 8 ⊢ (𝑥 ∈ ∪ (𝑅1 “ 𝐵) ↔ ∃𝑧 ∈ 𝐵 𝑥 ∈ (𝑅1‘𝑧))
30		df-rex 3090	. . . . . . . . 9 ⊢ (∃𝑧 ∈ 𝐵 𝑥 ∈ (𝑅1‘𝑧) ↔ ∃𝑧(𝑧 ∈ 𝐵 ∧ 𝑥 ∈ (𝑅1‘𝑧)))
31		rankr1ai 9766	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ (𝑅1‘𝑧) → (rank‘𝑥) ∈ 𝑧)
32		ordtr1 6405	. . . . . . . . . . . 12 ⊢ (Ord 𝐵 → (((rank‘𝑥) ∈ 𝑧 ∧ 𝑧 ∈ 𝐵) → (rank‘𝑥) ∈ 𝐵))
33	31, 32	sylani 615	. . . . . . . . . . 11 ⊢ (Ord 𝐵 → ((𝑥 ∈ (𝑅1‘𝑧) ∧ 𝑧 ∈ 𝐵) → (rank‘𝑥) ∈ 𝐵))
34	33	ancomsd 470	. . . . . . . . . 10 ⊢ (Ord 𝐵 → ((𝑧 ∈ 𝐵 ∧ 𝑥 ∈ (𝑅1‘𝑧)) → (rank‘𝑥) ∈ 𝐵))
35	34	exlimdv 1963	. . . . . . . . 9 ⊢ (Ord 𝐵 → (∃𝑧(𝑧 ∈ 𝐵 ∧ 𝑥 ∈ (𝑅1‘𝑧)) → (rank‘𝑥) ∈ 𝐵))
36	30, 35	biimtrid 245	. . . . . . . 8 ⊢ (Ord 𝐵 → (∃𝑧 ∈ 𝐵 𝑥 ∈ (𝑅1‘𝑧) → (rank‘𝑥) ∈ 𝐵))
37	29, 36	biimtrid 245	. . . . . . 7 ⊢ (Ord 𝐵 → (𝑥 ∈ ∪ (𝑅1 “ 𝐵) → (rank‘𝑥) ∈ 𝐵))
38	37	ralimdv 3179	. . . . . 6 ⊢ (Ord 𝐵 → (∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → ∀𝑥 ∈ 𝐴 (rank‘𝑥) ∈ 𝐵))
39	9, 38	syl 18	. . . . 5 ⊢ (Lim 𝐵 → (∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) → ∀𝑥 ∈ 𝐴 (rank‘𝑥) ∈ 𝐵))
40	39	impcom 412	. . . 4 ⊢ ((∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → ∀𝑥 ∈ 𝐴 (rank‘𝑥) ∈ 𝐵)
41	40	3adant1 1148	. . 3 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → ∀𝑥 ∈ 𝐴 (rank‘𝑥) ∈ 𝐵)
42		rankfilimbi 35504	. . 3 ⊢ (((𝐴 ∈ Fin ∧ 𝐴 ∈ ∪ (𝑅1 “ On)) ∧ (∀𝑥 ∈ 𝐴 (rank‘𝑥) ∈ 𝐵 ∧ Lim 𝐵)) → (rank‘𝐴) ∈ 𝐵)
43	27, 25, 41, 26, 42	syl22anc 851	. 2 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → (rank‘𝐴) ∈ 𝐵)
44		fveq2 6881	. . . . 5 ⊢ (𝑤 = suc (rank‘𝐴) → (𝑅1‘𝑤) = (𝑅1‘suc (rank‘𝐴)))
45	44	eleq2d 2849	. . . 4 ⊢ (𝑤 = suc (rank‘𝐴) → (𝐴 ∈ (𝑅1‘𝑤) ↔ 𝐴 ∈ (𝑅1‘suc (rank‘𝐴))))
46		limsuc 7841	. . . . . 6 ⊢ (Lim 𝐵 → ((rank‘𝐴) ∈ 𝐵 ↔ suc (rank‘𝐴) ∈ 𝐵))
47	46	biimpa 481	. . . . 5 ⊢ ((Lim 𝐵 ∧ (rank‘𝐴) ∈ 𝐵) → suc (rank‘𝐴) ∈ 𝐵)
48	47	3adant1 1148	. . . 4 ⊢ ((𝐴 ∈ ∪ (𝑅1 “ On) ∧ Lim 𝐵 ∧ (rank‘𝐴) ∈ 𝐵) → suc (rank‘𝐴) ∈ 𝐵)
49		rankidb 9768	. . . . 5 ⊢ (𝐴 ∈ ∪ (𝑅1 “ On) → 𝐴 ∈ (𝑅1‘suc (rank‘𝐴)))
50	49	3ad2ant1 1151	. . . 4 ⊢ ((𝐴 ∈ ∪ (𝑅1 “ On) ∧ Lim 𝐵 ∧ (rank‘𝐴) ∈ 𝐵) → 𝐴 ∈ (𝑅1‘suc (rank‘𝐴)))
51	45, 48, 50	rspcedvdw 3584	. . 3 ⊢ ((𝐴 ∈ ∪ (𝑅1 “ On) ∧ Lim 𝐵 ∧ (rank‘𝐴) ∈ 𝐵) → ∃𝑤 ∈ 𝐵 𝐴 ∈ (𝑅1‘𝑤))
52		eluniima 7248	. . . 4 ⊢ (Fun 𝑅1 → (𝐴 ∈ ∪ (𝑅1 “ 𝐵) ↔ ∃𝑤 ∈ 𝐵 𝐴 ∈ (𝑅1‘𝑤)))
53	6, 52	ax-mp 5	. . 3 ⊢ (𝐴 ∈ ∪ (𝑅1 “ 𝐵) ↔ ∃𝑤 ∈ 𝐵 𝐴 ∈ (𝑅1‘𝑤))
54	51, 53	sylibr 237	. 2 ⊢ ((𝐴 ∈ ∪ (𝑅1 “ On) ∧ Lim 𝐵 ∧ (rank‘𝐴) ∈ 𝐵) → 𝐴 ∈ ∪ (𝑅1 “ 𝐵))
55	25, 26, 43, 54	syl3anc 1398	1 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 𝑥 ∈ ∪ (𝑅1 “ 𝐵) ∧ Lim 𝐵) → 𝐴 ∈ ∪ (𝑅1 “ 𝐵))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 400   ∧ w3a 1103   = wceq 1570  ∃wex 1809   ∈ wcel 2143  ∀wral 3079  ∃wrex 3089   ⊆ wss 3905  ∪ cuni 4872  dom cdm 5661   “ cima 5664  Ord word 6359  Oncon0 6360  Lim wlim 6361  suc csuc 6362  Fun wfun 6530  ‘cfv 6536  Fincfn 8939  𝑅₁cr1 9730  rankcrnk 9731

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1825  ax-4 1839  ax-5 1940  ax-6 1997  ax-7 2038  ax-8 2145  ax-9 2153  ax-10 2176  ax-11 2192  ax-12 2213  ax-ext 2735  ax-rep 5238  ax-sep 5257  ax-nul 5269  ax-pow 5336  ax-pr 5404  ax-un 7732

This proof depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1810  df-nf 1814  df-sb 2097  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2838  df-nfc 2912  df-ne 2959  df-ral 3080  df-rex 3090  df-reu 3370  df-rab 3417  df-v 3457  df-sbc 3745  df-csb 3854  df-dif 3908  df-un 3910  df-in 3912  df-ss 3922  df-pss 3925  df-nul 4287  df-if 4488  df-pw 4564  df-sn 4590  df-pr 4592  df-op 4596  df-uni 4873  df-int 4913  df-iun 4958  df-br 5110  df-opab 5174  df-mpt 5193  df-tr 5219  df-id 5556  df-eprel 5561  df-po 5569  df-so 5570  df-fr 5614  df-we 5616  df-xp 5667  df-rel 5668  df-cnv 5669  df-co 5670  df-dm 5671  df-rn 5672  df-res 5673  df-ima 5674  df-pred 6302  df-ord 6363  df-on 6364  df-lim 6365  df-suc 6366  df-iota 6492  df-fun 6538  df-fn 6539  df-f 6540  df-f1 6541  df-fo 6542  df-f1o 6543  df-fv 6544  df-ov 7413  df-om 7859  df-1st 7982  df-2nd 7983  df-frecs 8274  df-wrecs 8305  df-recs 8354  df-rdg 8393  df-1o 8449  df-en 8940  df-dom 8941  df-fin 8943  df-r1 9732  df-rank 9733

This theorem is used by:  r1filim  35507  r1omhf  35509