Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 413: | \[2^{413}-1\] | 127 × 179951 × 2006647231 × 3203431780337<13> × 6774027833473375976915021445395839<34> × 21256743751927370220630952377105576570016395501658460697868351<62> |