Database
SUPPLEMENTARY MATERIAL (USERS' MATHBOXES)
Mathbox for Alexander van der Vekens
Even and odd numbers
Definitions and basic properties
evenp1odd
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oddp1eveni
Metamath Proof Explorer
Ascii
Unicode
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
∈
ℤ
2
1
peano2zd
⊢
Z
∈
Even
→
Z
+
1
∈
ℤ
3
iseven
⊢
Z
∈
Even
↔
Z
∈
ℤ
∧
Z
2
∈
ℤ
4
zcn
⊢
Z
∈
ℤ
→
Z
∈
ℂ
5
pncan1
⊢
Z
∈
ℂ
→
Z
+
1
-
1
=
Z
6
4
5
syl
⊢
Z
∈
ℤ
→
Z
+
1
-
1
=
Z
7
6
eqcomd
⊢
Z
∈
ℤ
→
Z
=
Z
+
1
-
1
8
7
oveq1d
⊢
Z
∈
ℤ
→
Z
2
=
Z
+
1
-
1
2
9
8
eleq1d
⊢
Z
∈
ℤ
→
Z
2
∈
ℤ
↔
Z
+
1
-
1
2
∈
ℤ
10
9
biimpa
⊢
Z
∈
ℤ
∧
Z
2
∈
ℤ
→
Z
+
1
-
1
2
∈
ℤ
11
3
10
sylbi
⊢
Z
∈
Even
→
Z
+
1
-
1
2
∈
ℤ
12
isodd2
⊢
Z
+
1
∈
Odd
↔
Z
+
1
∈
ℤ
∧
Z
+
1
-
1
2
∈
ℤ
13
2
11
12
sylanbrc
⊢
Z
∈
Even
→
Z
+
1
∈
Odd