Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 206: | \[{3^{206}-1\over2}\] | 22 × 619 × 3661040653 × 1535090713229126909942383374434289901<37> × 6957596529882152968992225251835887181478451547013<49> |