Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 840: | \[{21^{840}-1\over20}\] | 23 × 5 × 11 × 13 × 17 × 29 × 31 × 41 × 43 × 61 × 71 × 73 × 211 × 281 × 337 × 421 × 463 × 601 × 617 × 631 × 1471 × 2551 × 3181 × 3319 × 3697 × 4789 × 6427 × 9391 × 18181 × 18481 × 20161 × 33601 × 40841 × 50261 × 97241 × 140351 × 185641 × 501001 × 912521 × 1360861 × 3441241 × 4149601 × 4325861 × 7658113 × 20028751 × 40086001 × 78555121 × 81090871 × 81867661 × 126663601 × 227633407 × 518118697 × 920421641 × 2616115321 × 3987476221 × 16128844201<11> × 56819827681<11> × 68454248717<11> × 92152520881<11> × 115593326297<12> × 266902182961<12> × 831380909129<12> × 22864311556633<14> × 415710882920521<15> × 421503321597121<15> × 1053606939618901<16> × 2011123862511121<16> × 72413241922093801<17> × 6474775133349148921<19> × 428657635595589188881<21> × 5124240195826801224421<22> × 268004127903031206150241<24> × 1855106691418101398774071<25> × 32071033873519074932758681<26> × [283799369694093440777925520410524861181610389150515701550036858372619140051199564754833277132730871361103493954080119066427382563050439125336468517952976178723506932165913015645493548989421013902575130454868955149787335499251251558191815299543908585215732997573398234156535342647419526820710073292138092794968982501301954054623768085239976338942643681834689019907397638478274100451586649379402519737151361744529931016810682371136374924193002027187590889404676452539140405953727036562561763321090748397954596754578193970828074025883018576827297061420007010946423417<564>] |