Theorem nnn0

Description: The set of positive integers is nonempty. (Contributed by Glauco Siliprandi, 8-Apr-2021)

	Ref	Expression
Assertion	nnn0	⊢ ℕ ≠ ∅

Proof

Step	Hyp	Ref	Expression
1		1nn	⊢ 1 ∈ ℕ
2	1	ne0ii	⊢ ℕ ≠ ∅