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Metamath Proof Explorer

Theorem 9nn0

Description: 9 is a nonnegative integer. (Contributed by Mario Carneiro, 19-Apr-2015)

		Ref	Expression
	Assertion	9nn0	$⊢ 9 \in ℕ_{0}$

Step	Hyp	Ref	Expression
1		9nn	$⊢ 9 \in ℕ$
2	1	nnnn0i	$⊢ 9 \in ℕ_{0}$