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Metamath Proof Explorer

Theorem nnct

Description: NN is countable. (Contributed by Thierry Arnoux, 29-Dec-2016)

		Ref	Expression
	Assertion	nnct	$⊢ ℕ ≼ ω$

Step	Hyp	Ref	Expression
1		nnenom	$⊢ ℕ \approx ω$
2		endom	$⊢ ℕ \approx ω \to ℕ ≼ ω$
3	1 2	ax-mp	$⊢ ℕ ≼ ω$