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Related theorems GIF version |
| Description: Extend class notation to include class abstractions of ordered pairs. |
| Ref | Expression |
|---|---|
| wph | wff φ |
| vx | set x |
| vy | set y |
| Ref | Expression |
|---|---|
| copab | class {〈x, y〉∣φ} |
| Colors of variables: wff set class |