Base 2 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 415: | \[2^{415}-1\] | 31 × 167 × 470933694191<12> × 3028917598961<13> × 130666175908831<15> × 57912614113275649087721<23> × 32367218471375835379289471<26> × 46782247616476922972329742136208001<35> |