Theorem 12nn0

Description: 12 is a nonnegative integer. (Contributed by Umit Teoman Dogan, 10-Jun-2026)

	Ref	Expression
Assertion	12nn0	⊢ ; 1 2 ∈ ℕ0

Proof

Step	Hyp	Ref	Expression
1		1nn0	⊢ 1 ∈ ℕ0
2		2nn0	⊢ 2 ∈ ℕ0
3	1 2	deccl	⊢ ; 1 2 ∈ ℕ0