Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 377: | \[{21^{377}-1\over20}\] | 59 × 79 × 189437 × 23266933 × 516094151 × 1103704099 × 246763300513<12> × 687613372491653<15> × [75466566661289096366617674801066054113349070251272651587862871371853047574446245753676160536033956329544378174841817693047225899051029213401762275330757150756001768740085727169225708516983689966963646263836900783399474571013283182991780863452025841890388392550515286508092000038883005222843589219165494076560942130610268818398465116319483191804392387557731819543036402607592791758339099803400816261845089755414638989991771416863402409917<437>] |