Description: A nonnegative integer is an integer. (Contributed by NM, 9-May-2004)
Ref | Expression | ||
---|---|---|---|
Assertion | nn0z | $${\u22a2}{N}\in {\mathbb{N}}_{0}\to {N}\in \mathbb{Z}$$ |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nn0ssz | $${\u22a2}{\mathbb{N}}_{0}\subseteq \mathbb{Z}$$ | |
2 | 1 | sseli | $${\u22a2}{N}\in {\mathbb{N}}_{0}\to {N}\in \mathbb{Z}$$ |