Base 15 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 107: | \[{15^{107}-1\over14}\] | 643 × 1499 × 194527 × 609913483 × 17221279121951<14> × 8296079506365811612150733<25> × 8238863910860240211186514584551<31> × 368612716550576240747224386242176921<36> |