Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 207: | \[{3^{207}-1\over2}\] | 13 × 47 × 277 × 757 × 829 × 1657 × 4969 × 1001523179 × 2461243576713869557<19> × 134738353536933730552513618349505999724046176185208477<54> |