Base 8 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 247: | \[{8^{247}-1\over7}\] | 79 × 8191 × 15809 × 32377 × 121369 × 524287 × 1212847 × 83352127 × 6459570124697<13> × 402004106269663<15> × 2665675660861389884202429169<28> × 1282816117617265060453496956212169<34> × 87341035411411371841151965953966466102952126244970250385834048606070060716959754108184194109897<95> |