Metamath Proof Explorer


Theorem nnne0s

Description: A surreal positive integer is nonzero. (Contributed by Scott Fenton, 15-Apr-2025)

Ref Expression
Assertion nnne0s ( 𝐴 ∈ ℕs → 𝐴 ≠ 0s )

Proof

Step Hyp Ref Expression
1 eldifsni ⊢ ( 𝐴 ∈ ( ℕ0s ∖ { 0s } ) → 𝐴 ≠ 0s )
2 df-nns ⊢ ℕs = ( ℕ0s ∖ { 0s } )
3 1 2 eleq2s ⊢ ( 𝐴 ∈ ℕs → 𝐴 ≠ 0s )