Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 156: | \[{20^{156}-1\over19}\] | 32 × 7 × 132 × 53 × 79 × 127 × 157 × 401 × 421 × 1171 × 2081 × 2549 × 3121 × 12277 × 142559 × 502321 × 1340743 × 9690539 × 571945141 × 735408649 × 670533425797<12> × 22969682841393367<17> × 106896982629956973639277<24> × 628605693732325702045277<24> × 1928835910218750775722169<25> × 172311318287603732461390609<27> |