Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 253: | \[{3^{253}-1\over2}\] | 232 × 47 × 3851 × 1001523179 × 38636905168680714294388463<26> × 694795605450302885931482069023906496640308871072578393444435496767723247212161<78> |