Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 430: | \[{21^{430}-1\over20}\] | 2 × 5 × 11 × 173 × 431 × 1291 × 1721 × 3011 × 13331 × 15739 × 40841 × 126851 × 185641 × 1759991 × 117423401111<12> × 169367548429<12> × 1163308526467<13> × 3379774626131<13> × 32108273175191<14> × 222756144763231<15> × 31449579712763966011<20> × 478811691676843729951<21> × 35842614220783025524408588074144786493150233831596714503<56> × 22458563136234653946962711350413476174257597477220422525366810641122764279379275739271084832394659259740740662689132467112555210587805411689733019761086584237191<161> × [13562599955176353510116932638420458071565457554655268437338931646916920143663769327768863717647580420852895912822766242059684418900050381749616225265431658758039362408990835103490754726347731<191>] |