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| Mirrors > Home > MPE Home > Th. List > csb | Structured version Visualization version GIF version | ||
| Description: Extend class notation to include the proper substitution of a class for a set into another class. |
| Ref | Expression |
|---|---|
| vx | setvar 𝑥 |
| cA | class 𝐴 |
| cB | class 𝐵 |
| Ref | Expression |
|---|---|
| csb | class ⦋𝐴 / 𝑥⦌𝐵 |
| Colors of variables: wff setvar class |
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