Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 188: | \[{21^{188}-1\over20}\] | 22 × 11 × 13 × 17 × 283 × 1129 × 2069 × 49727 × 227011 × 10165349 × 32036611 × 75042551 × 158545759 × 5298873343<10> × 230199028303<12> × 2482265166773333982451717<25> × 9794718038248648833094153<25> × 264564425522789761284612235919<30> × 8562148818687129859327199364465468655642070625259011542401109720925808937715188723350576775777<94> |