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Description: Membership in an ordered-pair class abstraction defined by a restricted binary relation. (Contributed by AV, 16-Feb-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | elopabran |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | simpl | ||
| 2 | 1 | ssopab2i | |
| 3 | opabss | ||
| 4 | 2 3 | sstri | |
| 5 | 4 | sseli |