Metamath Proof Explorer


Theorem 2dvdsoddp1

Description: 2 divides an odd number increased by 1. (Contributed by AV, 18-Jun-2020)

Ref Expression
Assertion 2dvdsoddp1 ( 𝑍 ∈ Odd → 2 ∥ ( 𝑍 + 1 ) )

Proof

Step Hyp Ref Expression
1 2ndvdsodd ( 𝑍 ∈ Odd → ¬ 2 ∥ 𝑍 )
2 oddz ( 𝑍 ∈ Odd → 𝑍 ∈ ℤ )
3 oddp1even ( 𝑍 ∈ ℤ → ( ¬ 2 ∥ 𝑍 ↔ 2 ∥ ( 𝑍 + 1 ) ) )
4 2 3 syl ( 𝑍 ∈ Odd → ( ¬ 2 ∥ 𝑍 ↔ 2 ∥ ( 𝑍 + 1 ) ) )
5 1 4 mpbid ( 𝑍 ∈ Odd → 2 ∥ ( 𝑍 + 1 ) )