Description: Closure of exponentiation of nonnegative integers. (Contributed by Mario Carneiro, 17-Apr-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | nn0expcli.1 | ⊢ 𝐴 ∈ ℕ0 | |
| nn0expcli.2 | ⊢ 𝑁 ∈ ℕ0 | ||
| Assertion | nn0expcli | ⊢ ( 𝐴 ↑ 𝑁 ) ∈ ℕ0 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | nn0expcli.1 | ⊢ 𝐴 ∈ ℕ0 | |
| 2 | nn0expcli.2 | ⊢ 𝑁 ∈ ℕ0 | |
| 3 | nn0expcl | ⊢ ( ( 𝐴 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0 ) → ( 𝐴 ↑ 𝑁 ) ∈ ℕ0 ) | |
| 4 | 1 2 3 | mp2an | ⊢ ( 𝐴 ↑ 𝑁 ) ∈ ℕ0 |