Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 196: | \[{21^{196}-1\over20}\] | 22 × 11 × 13 × 17 × 29 × 43 × 197 × 631 × 1373 × 3319 × 3697 × 7057 × 266953 × 25268713 × 81867661 × 68454248717<11> × 1606344741163<13> × 1767442850839<13> × 2524084462789<13> × 86494371600108393937<20> × 1177455793090616585141<22> × 156357474589352978545297<24> × 1703751007820049542146461103<28> × 542402215683980150442690137563795758172071608525405860609723655091935189<72> |