Description: Membership in a power class. Theorem 86 of Suppes p. 47. See also elpw2g . (Contributed by NM, 6-Aug-2000) (Proof shortened by BJ, 31-Dec-2023)
Ref | Expression | ||
---|---|---|---|
Assertion | elpwg | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sseq1 | |
|
2 | df-pw | |
|
3 | 1 2 | elab2g | |