Base 13 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 91: | \[{13^{91}-1\over12}\] | 53 × 10193 × 34763 × 264031 × 1326781 × 1803647 × 5229043 × 72019220497491955875703699<26> × 4360058677522333400302555160685378238981<40> |