Metamath Proof Explorer
Description: A positive integer is even or odd but not both. (Contributed by NM, 1-Jan-2006) (Revised by AV, 19-Jun-2020)
|
|
Ref |
Expression |
|
Assertion |
nneoALTV |
⊢ ( 𝑁 ∈ ℕ → ( 𝑁 ∈ Even ↔ ¬ 𝑁 ∈ Odd ) ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
nnz |
⊢ ( 𝑁 ∈ ℕ → 𝑁 ∈ ℤ ) |
2 |
|
zeo2ALTV |
⊢ ( 𝑁 ∈ ℤ → ( 𝑁 ∈ Even ↔ ¬ 𝑁 ∈ Odd ) ) |
3 |
1 2
|
syl |
⊢ ( 𝑁 ∈ ℕ → ( 𝑁 ∈ Even ↔ ¬ 𝑁 ∈ Odd ) ) |