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Metamath Proof Explorer

Theorem nnord

Description: A natural number is ordinal. (Contributed by NM, 17-Oct-1995)

		Ref	Expression
	Assertion	nnord	$⊢ A \in ω \to Ord A$

Step	Hyp	Ref	Expression
1		nnon	$⊢ A \in ω \to A \in On$
2		eloni	$⊢ A \in On \to Ord A$
3	1 2	syl	$⊢ A \in ω \to Ord A$