Base 31 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 86: | \[{31^{86}-1\over30}\] | 25 × 173 × 146982701137<12> × 3049055684506560663410351046998584180840895763387409<52> × 2428604265313757770804574128250982331185007279645995324037847<61> |