Metamath Proof Explorer


Theorem nnge1d

Description: A positive integer is one or greater. (Contributed by Mario Carneiro, 27-May-2016)

Ref Expression
Hypothesis nnge1d.1 φA
Assertion nnge1d φ1A

Proof

Step Hyp Ref Expression
1 nnge1d.1 φA
2 nnge1 A1A
3 1 2 syl φ1A