Base 31 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 76: | \[{31^{76}-1\over30}\] | 26 × 13 × 37 × 191 × 571 × 1217 × 14251 × 23126269 × 53489941 × 2491389137 × 88770666332610762169<20> × 3545592640701962728192781<25> × 130154580611883020628409201<27> |