Metamath Proof Explorer


Theorem 2noddALTV

Description: 2 is not an odd number. (Contributed by AV, 3-Feb-2020) (Revised by AV, 18-Jun-2020)

Ref Expression
Assertion 2noddALTV 2 ∉ Odd

Proof

Step Hyp Ref Expression
1 2evenALTV 2 ∈ Even
2 df-nel ( 2 ∉ Odd ↔ ¬ 2 ∈ Odd )
3 2z 2 ∈ ℤ
4 zeo2ALTV ( 2 ∈ ℤ → ( 2 ∈ Even ↔ ¬ 2 ∈ Odd ) )
5 4 bicomd ( 2 ∈ ℤ → ( ¬ 2 ∈ Odd ↔ 2 ∈ Even ) )
6 3 5 ax-mp ( ¬ 2 ∈ Odd ↔ 2 ∈ Even )
7 2 6 bitri ( 2 ∉ Odd ↔ 2 ∈ Even )
8 1 7 mpbir 2 ∉ Odd