Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 316: | \[{21^{316}-1\over20}\] | 22 × 11 × 13 × 17 × 317 × 2687 × 10903 × 265757 × 1926854873 × 15208288358346544216626697<26> × 49710933021782204453685378593<29> × 34461495993387250259782587818586917<35> × 122435283552586211204658864416622901<36> × 261513239159154440967606433092726647<36> × 41784481746279594641483665441943191140798018660203<50> × 310374893244028301475836717855447777747952185668931927<54> × 662288596322631101390866583120656003068752177256160401293534059563466897600754122343099283790171164929002043426185589238140213<126> |