Base 15 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 215: | \[{15^{215}-1\over14}\] | 11 × 431 × 4931 × 1833802200566194141<19> × 4814957964951736081<19> × 4975400197345478916839425015315256265857101<43> × 26656068987980386414408582952871386493955339704241<50> × 2596855758588151053898863550500681735472021353969461351<55> × 7272282873616636486248750610008322442226145351765444154226961<61> |