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Related theorems GIF version |
| Description: Extend wff notation to include the general binary relation predicate. Note that the syntax is simply three class symbols in a row. |
| Ref | Expression |
|---|---|
| cA | class A |
| cB | class B |
| cR | class R |
| Ref | Expression |
|---|---|
| wbr | wff ARB |
| Colors of variables: wff set class |