Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 199: | \[{3^{199}-1\over2}\] | 1360648969 × 293366430131930353811221418233<30> × 110902970953020998760372036298330712066931713186888935429<57> |