Description: A "Godel-set of membership" is a member of a doubled Cartesian product. (Contributed by AV, 16-Sep-2023)
Ref | Expression | ||
---|---|---|---|
Assertion | goelel3xp | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | goel | |
|
2 | peano1 | |
|
3 | 2 | a1i | |
4 | opelxpi | |
|
5 | 3 4 | opelxpd | |
6 | 1 5 | eqeltrd | |