Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 284: | \[{20^{284}-1\over19}\] | 3 × 7 × 401 × 569 × 17041 × 53827373 × 3068721247 × 201161092255316201234202042361<30> × 496641441599935258407636234413<30> × 3389724375173873063832460218247<31> × 1899661864476214974784422964016709719864855214061<49> × 662247334433686993635651204693256092552098489826256721<54> × 61777752739108975259079961779208763786873373427879250247440461<62> × 460843615810484255929284510273557393889324216008345540739853468610844181393388120664809<87> |