Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 416: | \[{21^{416}-1\over20}\] | 25 × 11 × 132 × 17 × 53 × 79 × 1217 × 2689 × 31873 × 32969 × 62897 × 97241 × 101089 × 189437 × 300673 × 516094151 × 6857635489<10> × 1065309498241<13> × 258204094212481<15> × 7021471715414521<16> × 23509884574335185209<20> × 1615033161089271825038593<25> × 2927682077813715874149933185385605053168690918973651083914101281<64> × 5307265944045344592866344390398344961458517154690505360905068553502455652805329365975538762599355155777<103> × [267094942939048865829305833550917173222458861040871773311309008957942171815364928794937137644254598359808579756464801146780093214833909989223337131299199282644085924333713120749089793005951215627313505761852942875174405644822401<228>] |