Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 209: | \[{3^{209}-1\over2}\] | 23 × 419 × 1597 × 2927 × 3851 × 363889 × 99381983898121<14> × 340838185560681043030809047<27> × 1222487396439951792867078883996125166979<40> |