Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 248: | \[{20^{248}-1\over19}\] | 3 × 7 × 311 × 373 × 401 × 11161 × 40487 × 75269 × 160001 × 1646101 × 340037881769<12> × 10380943331569<14> × 111160667194373<15> × 581740080393079<15> × 335566676799518320433573040127<30> × 27736737856153197269675584866568095122351352801389778813467369<62> × 128044210020840514088975909188700984353890177041214308765685230699539552604360922582935315585474492996671966910176784162829823276342955465760529<144> |