Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 305: | \[{3^{305}-1\over2}\] | 112 × 65881 × 603901 × 4919054377091<13> × 105293313660391861035901<24> × 46229214937048975901175732207117334435811<41> × 144292067692894029928776589038168491785927205865834517921<57> |