Theorem eldifsucnn 8698

Description: Condition for membership in the difference of ω and a nonzero finite ordinal. (Contributed by Scott Fenton, 24-Oct-2024.)

Assertion

Ref	Expression
eldifsucnn	⊢ (𝐴 ∈ ω → (𝐵 ∈ (ω ∖ suc 𝐴) ↔ ∃𝑥 ∈ (ω ∖ 𝐴)𝐵 = suc 𝑥))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem eldifsucnn

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		peano2 7922	. . . . . 6 ⊢ (𝐴 ∈ ω → suc 𝐴 ∈ ω)
2		nnawordex 8671	. . . . . 6 ⊢ ((suc 𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (suc 𝐴 ⊆ 𝐵 ↔ ∃𝑦 ∈ ω (suc 𝐴 +o 𝑦) = 𝐵))
3	1, 2	sylan 592	. . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (suc 𝐴 ⊆ 𝐵 ↔ ∃𝑦 ∈ ω (suc 𝐴 +o 𝑦) = 𝐵))
4		nnacl 8645	. . . . . . . . 9 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (𝐴 +o 𝑦) ∈ ω)
5		nnaword1 8663	. . . . . . . . 9 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → 𝐴 ⊆ (𝐴 +o 𝑦))
6		nnasuc 8640	. . . . . . . . . . 11 ⊢ ((𝑦 ∈ ω ∧ 𝐴 ∈ ω) → (𝑦 +o suc 𝐴) = suc (𝑦 +o 𝐴))
7	6	ancoms 464	. . . . . . . . . 10 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (𝑦 +o suc 𝐴) = suc (𝑦 +o 𝐴))
8		nnacom 8651	. . . . . . . . . . 11 ⊢ ((suc 𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (suc 𝐴 +o 𝑦) = (𝑦 +o suc 𝐴))
9	1, 8	sylan 592	. . . . . . . . . 10 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (suc 𝐴 +o 𝑦) = (𝑦 +o suc 𝐴))
10		nnacom 8651	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (𝐴 +o 𝑦) = (𝑦 +o 𝐴))
11		suceq 6446	. . . . . . . . . . 11 ⊢ ((𝐴 +o 𝑦) = (𝑦 +o 𝐴) → suc (𝐴 +o 𝑦) = suc (𝑦 +o 𝐴))
12	10, 11	syl 18	. . . . . . . . . 10 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → suc (𝐴 +o 𝑦) = suc (𝑦 +o 𝐴))
13	7, 9, 12	3eqtr4d 2808	. . . . . . . . 9 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (suc 𝐴 +o 𝑦) = suc (𝐴 +o 𝑦))
14		sseq2 3939	. . . . . . . . . . 11 ⊢ (𝑥 = (𝐴 +o 𝑦) → (𝐴 ⊆ 𝑥 ↔ 𝐴 ⊆ (𝐴 +o 𝑦)))
15		suceq 6446	. . . . . . . . . . . 12 ⊢ (𝑥 = (𝐴 +o 𝑦) → suc 𝑥 = suc (𝐴 +o 𝑦))
16	15	eqeq2d 2774	. . . . . . . . . . 11 ⊢ (𝑥 = (𝐴 +o 𝑦) → ((suc 𝐴 +o 𝑦) = suc 𝑥 ↔ (suc 𝐴 +o 𝑦) = suc (𝐴 +o 𝑦)))
17	14, 16	anbi12d 644	. . . . . . . . . 10 ⊢ (𝑥 = (𝐴 +o 𝑦) → ((𝐴 ⊆ 𝑥 ∧ (suc 𝐴 +o 𝑦) = suc 𝑥) ↔ (𝐴 ⊆ (𝐴 +o 𝑦) ∧ (suc 𝐴 +o 𝑦) = suc (𝐴 +o 𝑦))))
18	17	rspcev 3580	. . . . . . . . 9 ⊢ (((𝐴 +o 𝑦) ∈ ω ∧ (𝐴 ⊆ (𝐴 +o 𝑦) ∧ (suc 𝐴 +o 𝑦) = suc (𝐴 +o 𝑦))) → ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ (suc 𝐴 +o 𝑦) = suc 𝑥))
19	4, 5, 13, 18	syl12anc 850	. . . . . . . 8 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ (suc 𝐴 +o 𝑦) = suc 𝑥))
20		eqeq1 2767	. . . . . . . . . 10 ⊢ ((suc 𝐴 +o 𝑦) = 𝐵 → ((suc 𝐴 +o 𝑦) = suc 𝑥 ↔ 𝐵 = suc 𝑥))
21	20	anbi2d 642	. . . . . . . . 9 ⊢ ((suc 𝐴 +o 𝑦) = 𝐵 → ((𝐴 ⊆ 𝑥 ∧ (suc 𝐴 +o 𝑦) = suc 𝑥) ↔ (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
22	21	rexbidv 3190	. . . . . . . 8 ⊢ ((suc 𝐴 +o 𝑦) = 𝐵 → (∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ (suc 𝐴 +o 𝑦) = suc 𝑥) ↔ ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
23	19, 22	syl5ibcom 248	. . . . . . 7 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → ((suc 𝐴 +o 𝑦) = 𝐵 → ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
24	23	rexlimdva 3167	. . . . . 6 ⊢ (𝐴 ∈ ω → (∃𝑦 ∈ ω (suc 𝐴 +o 𝑦) = 𝐵 → ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
25	24	adantr 486	. . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (∃𝑦 ∈ ω (suc 𝐴 +o 𝑦) = 𝐵 → ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
26	3, 25	sylbid 243	. . . 4 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (suc 𝐴 ⊆ 𝐵 → ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
27	26	expimpd 459	. . 3 ⊢ (𝐴 ∈ ω → ((𝐵 ∈ ω ∧ suc 𝐴 ⊆ 𝐵) → ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
28		peano2 7922	. . . . . . . 8 ⊢ (𝑥 ∈ ω → suc 𝑥 ∈ ω)
29	28	ad2antlr 740	. . . . . . 7 ⊢ (((𝐴 ∈ ω ∧ 𝑥 ∈ ω) ∧ 𝐴 ⊆ 𝑥) → suc 𝑥 ∈ ω)
30		nnord 7906	. . . . . . . . 9 ⊢ (𝐴 ∈ ω → Ord 𝐴)
31		nnord 7906	. . . . . . . . 9 ⊢ (𝑥 ∈ ω → Ord 𝑥)
32		ordsucsssuc 7855	. . . . . . . . 9 ⊢ ((Ord 𝐴 ∧ Ord 𝑥) → (𝐴 ⊆ 𝑥 ↔ suc 𝐴 ⊆ suc 𝑥))
33	30, 31, 32	syl2an 608	. . . . . . . 8 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → (𝐴 ⊆ 𝑥 ↔ suc 𝐴 ⊆ suc 𝑥))
34	33	biimpa 482	. . . . . . 7 ⊢ (((𝐴 ∈ ω ∧ 𝑥 ∈ ω) ∧ 𝐴 ⊆ 𝑥) → suc 𝐴 ⊆ suc 𝑥)
35	29, 34	jca 521	. . . . . 6 ⊢ (((𝐴 ∈ ω ∧ 𝑥 ∈ ω) ∧ 𝐴 ⊆ 𝑥) → (suc 𝑥 ∈ ω ∧ suc 𝐴 ⊆ suc 𝑥))
36		eleq1 2852	. . . . . . 7 ⊢ (𝐵 = suc 𝑥 → (𝐵 ∈ ω ↔ suc 𝑥 ∈ ω))
37		sseq2 3939	. . . . . . 7 ⊢ (𝐵 = suc 𝑥 → (suc 𝐴 ⊆ 𝐵 ↔ suc 𝐴 ⊆ suc 𝑥))
38	36, 37	anbi12d 644	. . . . . 6 ⊢ (𝐵 = suc 𝑥 → ((𝐵 ∈ ω ∧ suc 𝐴 ⊆ 𝐵) ↔ (suc 𝑥 ∈ ω ∧ suc 𝐴 ⊆ suc 𝑥)))
39	35, 38	syl5ibrcom 250	. . . . 5 ⊢ (((𝐴 ∈ ω ∧ 𝑥 ∈ ω) ∧ 𝐴 ⊆ 𝑥) → (𝐵 = suc 𝑥 → (𝐵 ∈ ω ∧ suc 𝐴 ⊆ 𝐵)))
40	39	expimpd 459	. . . 4 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → ((𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥) → (𝐵 ∈ ω ∧ suc 𝐴 ⊆ 𝐵)))
41	40	rexlimdva 3167	. . 3 ⊢ (𝐴 ∈ ω → (∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥) → (𝐵 ∈ ω ∧ suc 𝐴 ⊆ 𝐵)))
42	27, 41	impbid 215	. 2 ⊢ (𝐴 ∈ ω → ((𝐵 ∈ ω ∧ suc 𝐴 ⊆ 𝐵) ↔ ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
43		eldif 4052	. . 3 ⊢ (𝐵 ∈ (ω ∖ suc 𝐴) ↔ (𝐵 ∈ ω ∧ ¬ 𝐵 ∈ suc 𝐴))
44		nnord 7906	. . . . . 6 ⊢ (suc 𝐴 ∈ ω → Ord suc 𝐴)
45	1, 44	syl 18	. . . . 5 ⊢ (𝐴 ∈ ω → Ord suc 𝐴)
46		nnord 7906	. . . . 5 ⊢ (𝐵 ∈ ω → Ord 𝐵)
47		ordtri1 6411	. . . . 5 ⊢ ((Ord suc 𝐴 ∧ Ord 𝐵) → (suc 𝐴 ⊆ 𝐵 ↔ ¬ 𝐵 ∈ suc 𝐴))
48	45, 46, 47	syl2an 608	. . . 4 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (suc 𝐴 ⊆ 𝐵 ↔ ¬ 𝐵 ∈ suc 𝐴))
49	48	pm5.32da 590	. . 3 ⊢ (𝐴 ∈ ω → ((𝐵 ∈ ω ∧ suc 𝐴 ⊆ 𝐵) ↔ (𝐵 ∈ ω ∧ ¬ 𝐵 ∈ suc 𝐴)))
50	43, 49	bitr4id 293	. 2 ⊢ (𝐴 ∈ ω → (𝐵 ∈ (ω ∖ suc 𝐴) ↔ (𝐵 ∈ ω ∧ suc 𝐴 ⊆ 𝐵)))
51		eldif 4052	. . . . . 6 ⊢ (𝑥 ∈ (ω ∖ 𝐴) ↔ (𝑥 ∈ ω ∧ ¬ 𝑥 ∈ 𝐴))
52	51	anbi1i 636	. . . . 5 ⊢ ((𝑥 ∈ (ω ∖ 𝐴) ∧ 𝐵 = suc 𝑥) ↔ ((𝑥 ∈ ω ∧ ¬ 𝑥 ∈ 𝐴) ∧ 𝐵 = suc 𝑥))
53		anass 474	. . . . 5 ⊢ (((𝑥 ∈ ω ∧ ¬ 𝑥 ∈ 𝐴) ∧ 𝐵 = suc 𝑥) ↔ (𝑥 ∈ ω ∧ (¬ 𝑥 ∈ 𝐴 ∧ 𝐵 = suc 𝑥)))
54	52, 53	bitri 278	. . . 4 ⊢ ((𝑥 ∈ (ω ∖ 𝐴) ∧ 𝐵 = suc 𝑥) ↔ (𝑥 ∈ ω ∧ (¬ 𝑥 ∈ 𝐴 ∧ 𝐵 = suc 𝑥)))
55	54	rexbii2 3109	. . 3 ⊢ (∃𝑥 ∈ (ω ∖ 𝐴)𝐵 = suc 𝑥 ↔ ∃𝑥 ∈ ω (¬ 𝑥 ∈ 𝐴 ∧ 𝐵 = suc 𝑥))
56		ordtri1 6411	. . . . . 6 ⊢ ((Ord 𝐴 ∧ Ord 𝑥) → (𝐴 ⊆ 𝑥 ↔ ¬ 𝑥 ∈ 𝐴))
57	30, 31, 56	syl2an 608	. . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → (𝐴 ⊆ 𝑥 ↔ ¬ 𝑥 ∈ 𝐴))
58	57	anbi1d 643	. . . 4 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → ((𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥) ↔ (¬ 𝑥 ∈ 𝐴 ∧ 𝐵 = suc 𝑥)))
59	58	rexbidva 3188	. . 3 ⊢ (𝐴 ∈ ω → (∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥) ↔ ∃𝑥 ∈ ω (¬ 𝑥 ∈ 𝐴 ∧ 𝐵 = suc 𝑥)))
60	55, 59	bitr4id 293	. 2 ⊢ (𝐴 ∈ ω → (∃𝑥 ∈ (ω ∖ 𝐴)𝐵 = suc 𝑥 ↔ ∃𝑥 ∈ ω (𝐴 ⊆ 𝑥 ∧ 𝐵 = suc 𝑥)))
61	42, 50, 60	3bitr4d 314	1 ⊢ (𝐴 ∈ ω → (𝐵 ∈ (ω ∖ suc 𝐴) ↔ ∃𝑥 ∈ (ω ∖ 𝐴)𝐵 = suc 𝑥))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570   ∈ wcel 2147  ∃wrex 3090   ⊆ wss 3900   ∖ cdif 4048  Ord word 6376  suc csuc 6379  (class class class)co 7440  ωcom 7898   +_o coa 8498

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-10 2180  ax-11 2197  ax-12 2216  ax-ext 2735  ax-sep 5252  ax-nul 5263  ax-pr 5395  ax-un 7772

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2102  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3081  df-rex 3091  df-reu 3370  df-rab 3417  df-v 3456  df-sbc 3743  df-csb 3852  df-ss 3901  df-pss 4017  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-pw 4562  df-sn 4589  df-pr 4591  df-op 4839  df-uni 4871  df-int 4911  df-iun 4956  df-br 5107  df-opab 5171  df-mpt 5190  df-tr 5216  df-id 5550  df-eprel 5555  df-po 5563  df-so 5564  df-fr 5608  df-we 5610  df-xp 5661  df-rel 5662  df-cnv 5663  df-co 5664  df-dm 5665  df-rn 5666  df-res 5667  df-ima 5668  df-pred 6319  df-ord 6380  df-on 6381  df-lim 6382  df-suc 6383  df-iota 6509  df-fun 6557  df-fn 6558  df-f 6559  df-f1 6560  df-fo 6561  df-f1o 6562  df-fv 6563  df-ov 7443  df-oprab 7444  df-mpo 7445  df-om 7899  df-2nd 8023  df-frecs 8324  df-wrecs 8355  df-recs 8404  df-rdg 8443  df-oadd 8505

This theorem is used by:  brttrcl2  9739  ttrcltr  9741  rnttrcl  9747