Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 345: | \[{21^{345}-1\over20}\] | 5 × 47 × 211 × 463 × 1381 × 9391 × 18181 × 19597 × 40841 × 182851 × 282924347471791<15> × 459878292118921111<18> × 1322715809759301301<19> × 4007561439284483090161<22> × 139870566115103282847737<24> × 3394964812534556016503466037951<31> × 31179105887601949149105715319437017328831<41> × 162708209139159956445385758966200454982244714891163955510792310084461<69> × [55628083120943845691722717632712935233175689558572131790616992007938295180799934252746048920343516132800436769310766203427915333834948457241392629812126532893991919634063305327286482608751<188>] |