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Description: Binary relation for an ordered pair singleton. (Contributed by Thierry Arnoux, 23-Sep-2023)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | brsnop |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-br | ||
| 2 | opex | ||
| 3 | 2 | elsn | |
| 4 | opthg2 | ||
| 5 | 3 4 | bitrid | |
| 6 | 1 5 | bitrid |