Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
133: | \[{21^{133}-1\over20}\] | 43 × 631 × 3319 × 12061389013<11> × 54921106624003<14> × 948175293266954869500463698756935713088089028515629708586399<60> × 63329476461782882569173744712807443377466798335943392324014170553080956816124248119<83> |