Theorem nnsdomg 8770

Description: Omega strictly dominates a natural number. Example 3 of [Enderton] p. 146. In order to avoid the Axiom of infinity, we include it as a hypothesis. (Contributed by NM, 15-Jun-1998.)

Assertion

Ref	Expression
nnsdomg	⊢ ((ω ∈ V ∧ 𝐴 ∈ ω) → 𝐴 ≺ ω)

Proof of Theorem nnsdomg

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		ssdomg 8548	. . 3 ⊢ (ω ∈ V → (𝐴 ⊆ ω → 𝐴 ≼ ω))
2		ordom 7582	. . . 4 ⊢ Ord ω
3		ordelss 6200	. . . 4 ⊢ ((Ord ω ∧ 𝐴 ∈ ω) → 𝐴 ⊆ ω)
4	2, 3	mpan 688	. . 3 ⊢ (𝐴 ∈ ω → 𝐴 ⊆ ω)
5	1, 4	impel 508	. 2 ⊢ ((ω ∈ V ∧ 𝐴 ∈ ω) → 𝐴 ≼ ω)
6		ominf 8723	. . . 4 ⊢ ¬ ω ∈ Fin
7		ensym 8551	. . . . 5 ⊢ (𝐴 ≈ ω → ω ≈ 𝐴)
8		breq2 5063	. . . . . . . 8 ⊢ (𝑥 = 𝐴 → (ω ≈ 𝑥 ↔ ω ≈ 𝐴))
9	8	rspcev 3620	. . . . . . 7 ⊢ ((𝐴 ∈ ω ∧ ω ≈ 𝐴) → ∃𝑥 ∈ ω ω ≈ 𝑥)
10		isfi 8526	. . . . . . 7 ⊢ (ω ∈ Fin ↔ ∃𝑥 ∈ ω ω ≈ 𝑥)
11	9, 10	sylibr 236	. . . . . 6 ⊢ ((𝐴 ∈ ω ∧ ω ≈ 𝐴) → ω ∈ Fin)
12	11	ex 415	. . . . 5 ⊢ (𝐴 ∈ ω → (ω ≈ 𝐴 → ω ∈ Fin))
13	7, 12	syl5 34	. . . 4 ⊢ (𝐴 ∈ ω → (𝐴 ≈ ω → ω ∈ Fin))
14	6, 13	mtoi 201	. . 3 ⊢ (𝐴 ∈ ω → ¬ 𝐴 ≈ ω)
15	14	adantl 484	. 2 ⊢ ((ω ∈ V ∧ 𝐴 ∈ ω) → ¬ 𝐴 ≈ ω)
16		brsdom 8525	. 2 ⊢ (𝐴 ≺ ω ↔ (𝐴 ≼ ω ∧ ¬ 𝐴 ≈ ω))
17	5, 15, 16	sylanbrc 585	1 ⊢ ((ω ∈ V ∧ 𝐴 ∈ ω) → 𝐴 ≺ ω)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 398   ∈ wcel 2113  ∃wrex 3138  Vcvv 3491   ⊆ wss 3929   class class class wbr 5059  Ord word 6183  ωcom 7573   ≈ cen 8499   ≼ cdom 8500   ≺ csdm 8501  Fincfn 8502

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1969  ax-7 2014  ax-8 2115  ax-9 2123  ax-10 2144  ax-11 2160  ax-12 2176  ax-ext 2792  ax-sep 5196  ax-nul 5203  ax-pow 5259  ax-pr 5323  ax-un 7454

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3or 1083  df-3an 1084  df-tru 1539  df-ex 1780  df-nf 1784  df-sb 2069  df-mo 2621  df-eu 2653  df-clab 2799  df-cleq 2813  df-clel 2892  df-nfc 2962  df-ne 3016  df-ral 3142  df-rex 3143  df-rab 3146  df-v 3493  df-sbc 3769  df-dif 3932  df-un 3934  df-in 3936  df-ss 3945  df-pss 3947  df-nul 4285  df-if 4461  df-pw 4534  df-sn 4561  df-pr 4563  df-tp 4565  df-op 4567  df-uni 4832  df-br 5060  df-opab 5122  df-tr 5166  df-id 5453  df-eprel 5458  df-po 5467  df-so 5468  df-fr 5507  df-we 5509  df-xp 5554  df-rel 5555  df-cnv 5556  df-co 5557  df-dm 5558  df-rn 5559  df-res 5560  df-ima 5561  df-ord 6187  df-on 6188  df-lim 6189  df-suc 6190  df-iota 6307  df-fun 6350  df-fn 6351  df-f 6352  df-f1 6353  df-fo 6354  df-f1o 6355  df-fv 6356  df-om 7574  df-er 8282  df-en 8503  df-dom 8504  df-sdom 8505  df-fin 8506

This theorem is referenced by:  isfiniteg  8771  infsdomnn  8772  nnsdom  9110