Base 15 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
81: | \[{15^{81}-1\over14}\] | 109 × 163 × 241 × 541 × 21061 × 16354441 × 829049498029<12> × 19803428495911816157659521610469429585428513632230232098351227<62> |