Base 7 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 125: | \[{7^{125}-1\over6}\] | 251 × 2551 × 2801 × 31280679788951<14> × 2182816753758823696751<22> × 5903546678356844440204179342119473011887617239565323800435501<61> |