Description: An even number is an integer. (Contributed by AV, 14-Jun-2020)
Ref | Expression | ||
---|---|---|---|
Assertion | evenz | ⊢ ( 𝑍 ∈ Even → 𝑍 ∈ ℤ ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | iseven | ⊢ ( 𝑍 ∈ Even ↔ ( 𝑍 ∈ ℤ ∧ ( 𝑍 / 2 ) ∈ ℤ ) ) | |
2 | 1 | simplbi | ⊢ ( 𝑍 ∈ Even → 𝑍 ∈ ℤ ) |