Base 7 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
215: | \[{7^{215}-1\over6}\] | 2801 × 31391 × 822161 × 166003607842448777<18> × 2192537062271178641<19> × 11300176322829911971<20> × 147795410845880963171<21> × 11916717598664539151308306888803765941891<41> × 15808291449184578466328984491788528176755903275531421<53> |