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

Ref | Expression | ||
---|---|---|---|

Hypothesis | nnge1d.1 | $${\u22a2}{\phi}\to {A}\in \mathbb{N}$$ | |

Assertion | nngt0d | $${\u22a2}{\phi}\to 0<{A}$$ |

Step | Hyp | Ref | Expression |
---|---|---|---|

1 | nnge1d.1 | $${\u22a2}{\phi}\to {A}\in \mathbb{N}$$ | |

2 | nngt0 | $${\u22a2}{A}\in \mathbb{N}\to 0<{A}$$ | |

3 | 1 2 | syl | $${\u22a2}{\phi}\to 0<{A}$$ |