Theorem nnawordex 6806

Description: Equivalence for weak ordering of natural numbers. (Contributed by NM, 8-Nov-2002.) (Revised by Mario Carneiro, 15-Nov-2014.)

Assertion

Ref	Expression
nnawordex	⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 ⊆ 𝐵 ↔ ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem nnawordex

Step	Hyp	Ref	Expression
1		nntri3or 6770	. . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 ∈ 𝐵 ∨ 𝐴 = 𝐵 ∨ 𝐵 ∈ 𝐴))
2	1	3adant3 1048	. . . 4 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → (𝐴 ∈ 𝐵 ∨ 𝐴 = 𝐵 ∨ 𝐵 ∈ 𝐴))
3		nnaordex 6805	. . . . . . 7 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 ∈ 𝐵 ↔ ∃𝑥 ∈ ω (∅ ∈ 𝑥 ∧ (𝐴 +o 𝑥) = 𝐵)))
4		simpr 110	. . . . . . . 8 ⊢ ((∅ ∈ 𝑥 ∧ (𝐴 +o 𝑥) = 𝐵) → (𝐴 +o 𝑥) = 𝐵)
5	4	reximi 2647	. . . . . . 7 ⊢ (∃𝑥 ∈ ω (∅ ∈ 𝑥 ∧ (𝐴 +o 𝑥) = 𝐵) → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵)
6	3, 5	biimtrdi 163	. . . . . 6 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 ∈ 𝐵 → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵))
7	6	3adant3 1048	. . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → (𝐴 ∈ 𝐵 → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵))
8		nna0 6751	. . . . . . . 8 ⊢ (𝐴 ∈ ω → (𝐴 +o ∅) = 𝐴)
9	8	3ad2ant1 1049	. . . . . . 7 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → (𝐴 +o ∅) = 𝐴)
10		eqeq2 2248	. . . . . . 7 ⊢ (𝐴 = 𝐵 → ((𝐴 +o ∅) = 𝐴 ↔ (𝐴 +o ∅) = 𝐵))
11	9, 10	syl5ibcom 155	. . . . . 6 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → (𝐴 = 𝐵 → (𝐴 +o ∅) = 𝐵))
12		peano1 4743	. . . . . . 7 ⊢ ∅ ∈ ω
13		oveq2 6096	. . . . . . . . 9 ⊢ (𝑥 = ∅ → (𝐴 +o 𝑥) = (𝐴 +o ∅))
14	13	eqeq1d 2247	. . . . . . . 8 ⊢ (𝑥 = ∅ → ((𝐴 +o 𝑥) = 𝐵 ↔ (𝐴 +o ∅) = 𝐵))
15	14	rspcev 2929	. . . . . . 7 ⊢ ((∅ ∈ ω ∧ (𝐴 +o ∅) = 𝐵) → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵)
16	12, 15	mpan 428	. . . . . 6 ⊢ ((𝐴 +o ∅) = 𝐵 → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵)
17	11, 16	syl6 33	. . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → (𝐴 = 𝐵 → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵))
18		nntri1 6773	. . . . . . 7 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 ⊆ 𝐵 ↔ ¬ 𝐵 ∈ 𝐴))
19	18	biimp3a 1386	. . . . . 6 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → ¬ 𝐵 ∈ 𝐴)
20	19	pm2.21d 628	. . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → (𝐵 ∈ 𝐴 → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵))
21	7, 17, 20	3jaod 1345	. . . 4 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → ((𝐴 ∈ 𝐵 ∨ 𝐴 = 𝐵 ∨ 𝐵 ∈ 𝐴) → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵))
22	2, 21	mpd 13	. . 3 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ⊆ 𝐵) → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵)
23	22	3expia 1236	. 2 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 ⊆ 𝐵 → ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵))
24		nnaword1 6790	. . . . 5 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → 𝐴 ⊆ (𝐴 +o 𝑥))
25		sseq2 3272	. . . . 5 ⊢ ((𝐴 +o 𝑥) = 𝐵 → (𝐴 ⊆ (𝐴 +o 𝑥) ↔ 𝐴 ⊆ 𝐵))
26	24, 25	syl5ibcom 155	. . . 4 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → ((𝐴 +o 𝑥) = 𝐵 → 𝐴 ⊆ 𝐵))
27	26	rexlimdva 2668	. . 3 ⊢ (𝐴 ∈ ω → (∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵 → 𝐴 ⊆ 𝐵))
28	27	adantr 276	. 2 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵 → 𝐴 ⊆ 𝐵))
29	23, 28	impbid 129	1 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 ⊆ 𝐵 ↔ ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝐵))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 104   ↔ wb 105   ∨ w3o 1008   ∧ w3a 1009   = wceq 1402   ∈ wcel 2209  ∃wrex 2529   ⊆ wss 3220  ∅c0 3520  ωcom 4739  (class class class)co 6088   +_o coa 6688

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-coll 4248  ax-sep 4251  ax-nul 4261  ax-pow 4313  ax-pr 4348  ax-un 4580  ax-setind 4686  ax-iinf 4737

This proof depends on definitions:  df-bi 117  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-iun 4014  df-br 4132  df-opab 4194  df-mpt 4195  df-tr 4232  df-id 4440  df-iord 4513  df-on 4515  df-suc 4518  df-iom 4740  df-xp 4782  df-rel 4783  df-cnv 4784  df-co 4785  df-dm 4786  df-rn 4787  df-res 4788  df-ima 4789  df-iota 5340  df-fun 5382  df-fn 5383  df-f 5384  df-f1 5385  df-fo 5386  df-f1o 5387  df-fv 5388  df-ov 6091  df-oprab 6092  df-mpo 6093  df-1st 6378  df-2nd 6379  df-recs 6580  df-irdg 6645  df-1o 6691  df-oadd 6695

This theorem is used by:  prarloclemn  7872