Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 471: | \[{21^{471}-1\over20}\] | 463 × 94201 × 1284889 × 22283011 × 562990697 × 927769418893<12> × 771665274541267<15> × 334476044232700351<18> × 44482273166035426789<20> × 6340852464650001524284475768730383408507<40> × 36128673184132773582933876451093687972835000129153707924245857928468744525906461419912826363972237547111359700431261443<119> × [1697696108913919304927903245370010652576587490093268158277378420706518624272772393037372142069735052087257710831086918570759570104190907932288397950645599800618951824113338813439872169628101221141125406332217030924010131742660909784247920486565281849577124703418201438998203274706683985476869384827970750564500301650069801766634823055941533260317309964068078706039064251<370>] |