Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 386: | \[{21^{386}-1\over20}\] | 2 × 11 × 773 × 100747 × 470149 × 155123125453<12> × 16284846801239<14> × 38229676354673148794146401001<29> × [13008185462468519315377199077803103532203082983936426415674386525290108562039173577341825293441480745129960341626402980820816643272894763452860183817988444023889057805670929674811370063825201637651222270790452347901<215>] × [117617079685914527094854915214540055488491841262697858165297249000770508316531277488223419832893337089972578498568919422145109657897241670883199142157439942235154547651652069376076544608389426915730635597741083998879235619538781<228>] |