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REAL AND COMPLEX NUMBERS
Integer sets
Principle of mathematical induction
nnne0d
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Metamath Proof Explorer
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Theorem
nnne0d
Description:
A positive integer is nonzero.
(Contributed by
Mario Carneiro
, 27-May-2016)
Ref
Expression
Hypothesis
nnge1d.1
⊢
φ
→
A
∈
ℕ
Assertion
nnne0d
⊢
φ
→
A
≠
0
Proof
Step
Hyp
Ref
Expression
1
nnge1d.1
⊢
φ
→
A
∈
ℕ
2
nnne0
⊢
A
∈
ℕ
→
A
≠
0
3
1
2
syl
⊢
φ
→
A
≠
0