Base 8 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 261: | \[{8^{261}-1\over7}\] | 73 × 233 × 1103 × 1567 × 2089 × 4177 × 262657 × 9857737155463<13> × 602999957032279571271592229136193<33> × 1345967414522954303164296915490846371433<40> × 328017025014102923449988663752960080886511412965881<51> × 41100578385770666334376636934095140722443159255961483460436653394844713097287<77> |