Theorem 11nn

Description: 11 is a positive integer. (Contributed by Umit Teoman Dogan, 10-Jun-2026)

	Ref	Expression
Assertion	11nn	⊢ ; 1 1 ∈ ℕ

Proof

Step	Hyp	Ref	Expression
1		1nn0	⊢ 1 ∈ ℕ0
2		1nn	⊢ 1 ∈ ℕ
3	1 2	decnncl	⊢ ; 1 1 ∈ ℕ