Base 15 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
76: | \[{15^{76}-1\over14}\] | 25 × 113 × 229 × 13757 × 26297 × 4272113 × 18434831466377<14> × 370649274902657<15> × 439799488353587<15> × 4485532699379697977461729<25> |