Base 8 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 257: | \[{8^{257}-1\over7}\] | 1543 × 535006138814359<15> × 1155685395246619182673033<25> × 374550598501810936581776630096313181393<39> × 4965395030068548134274243124972075225434447114375481299036593442726326832727934403424309955102162841656341524725641213163998408700663382552888660520657<151> |