Description: The ring of integers is a nonzero ring. (Contributed by AV, 18-Apr-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | zringnzr | |- ZZring e. NzRing |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | zringring | |- ZZring e. Ring |
|
| 2 | ax-1ne0 | |- 1 =/= 0 |
|
| 3 | zring1 | |- 1 = ( 1r ` ZZring ) |
|
| 4 | zring0 | |- 0 = ( 0g ` ZZring ) |
|
| 5 | 3 4 | isnzr | |- ( ZZring e. NzRing <-> ( ZZring e. Ring /\ 1 =/= 0 ) ) |
| 6 | 1 2 5 | mpbir2an | |- ZZring e. NzRing |