Metamath Proof Explorer


Theorem n0expscl

Description: Closure law for non-negative surreal integer exponentiation. (Contributed by Scott Fenton, 7-Nov-2025)

Ref Expression
Assertion n0expscl ( ( 𝐴 ∈ ℕ0s ∧ 𝑁 ∈ ℕ0s ) → ( 𝐴 ↑s 𝑁 ) ∈ ℕ0s )

Proof

Step Hyp Ref Expression
1 n0ssno ⊢ ℕ0s ⊆ No
2 n0mulscl ⊢ ( ( 𝑥 ∈ ℕ0s ∧ 𝑦 ∈ ℕ0s ) → ( 𝑥 ·s 𝑦 ) ∈ ℕ0s )
3 1n0s ⊢ 1s ∈ ℕ0s
4 1 2 3 expscllem ⊢ ( ( 𝐴 ∈ ℕ0s ∧ 𝑁 ∈ ℕ0s ) → ( 𝐴 ↑s 𝑁 ) ∈ ℕ0s )