Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 349: | \[2^{349}-1\] | 1779973928671<13> × 34720396273212657799920861294559<32> × 18555393648630683868229284313709360336855095474246691696225599<62> |