Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 356: | \[{3^{356}-1\over2}\] | 23 × 5 × 179 × 264331 × 1125706177 × 1611479891519807<16> × 5042939439565996049162197<25> × 1192464167514295068582330293<28> × 2444322641415331355533344283<28> × 709803280757497203996320461865063802526226069876477910653<57> |