Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 242: | \[{21^{242}-1\over20}\] | 2 × 113 × 23 × 6073 × 10362529 × 32981213 × 50820727 × 45727370393<11> × 17513875027111<14> × 38524810489309<14> × 25400947557093092161<20> × 696345076410285727892694949942258081484370607564459<51> × 1229365411955472262108048132187482030871927613612042227<55> × 1094642996710826219735129227785915893367653427444929746456584017045151470091370769903278728324073277790247936858477306484443951<127> |