Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 431: | \[{4^{431}-1\over3}\] | 863 × 3449 × 36238481 × 76859369 × 558062249 × 4642152737<10> × 1807447391779<13> × 37452571239931<14> × 142850312799017452169<21> × 1807482391092819529831423005040763105191863029850140579776353298087457<70> × 27306093454857278136151466787158724903415193508113091644798914026250805107043994199261467851009282903867<104> |