Metamath Proof Explorer


Theorem evenp1odd

Description: The successor of an even number is odd. (Contributed by AV, 16-Jun-2020)

Ref Expression
Assertion evenp1odd Z Even Z + 1 Odd

Proof

Step Hyp Ref Expression
1 evenz Z Even Z
2 1 peano2zd Z Even Z + 1
3 iseven Z Even Z Z 2
4 zcn Z Z
5 pncan1 Z Z + 1 - 1 = Z
6 4 5 syl Z Z + 1 - 1 = Z
7 6 eqcomd Z Z = Z + 1 - 1
8 7 oveq1d Z Z 2 = Z + 1 - 1 2
9 8 eleq1d Z Z 2 Z + 1 - 1 2
10 9 biimpa Z Z 2 Z + 1 - 1 2
11 3 10 sylbi Z Even Z + 1 - 1 2
12 isodd2 Z + 1 Odd Z + 1 Z + 1 - 1 2
13 2 11 12 sylanbrc Z Even Z + 1 Odd