Description: Membership in a predecessor class. (Contributed by Scott Fenton, 4-Feb-2011)
Ref | Expression | ||
---|---|---|---|
Hypothesis | elpred.1 | ||
Assertion | elpred |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elpred.1 | ||
2 | df-pred | ||
3 | 2 | elin2 | |
4 | 1 | eliniseg | |
5 | 4 | anbi2d | |
6 | 3 5 | syl5bb |