Theorem nnoni 7867

Description: A natural number is an ordinal number. (Contributed by NM, 27-Jun-1994.)

Hypothesis

Ref	Expression
nnoni.1	⊢ 𝐴 ∈ ω

Assertion

Ref	Expression
nnoni	⊢ 𝐴 ∈ On

Proof of Theorem nnoni

Step	Hyp	Ref	Expression
1		nnoni.1	. 2 ⊢ 𝐴 ∈ ω
2		nnon 7866	. 2 ⊢ (𝐴 ∈ ω → 𝐴 ∈ On)
3	1, 2	ax-mp 5	1 ⊢ 𝐴 ∈ On

This proof depends on syntax axioms:   ∈ wcel 2142  Oncon0 6360  ωcom 7860

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-8 2144  ax-9 2152  ax-ext 2734

This proof depends on definitions:  df-bi 210  df-an 401  df-ex 1809  df-sb 2096  df-clab 2741  df-cleq 2754  df-clel 2837  df-rab 3416  df-ss 3921  df-om 7861

This theorem is used by:  omopthlem1  8643  omopthlem2  8644  omopthi  8645