Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 321: | \[{3^{321}-1\over2}\] | 13 × 3853 × 6421 × 50077 × 229837 × 1276775957917<13> × 48965028505045123993421250406516036571557<41> × 3093775405140043883292950219372796456737513003762298030441588628306854600509966509<82> |