This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: The successor of a set is a set (generalization). (Contributed by NM, 5-Jun-1994)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | sucexg |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elex | ||
| 2 | sucexb | ||
| 3 | 1 2 | sylib |