Base 18 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 215: | \[{18^{215}-1\over17}\] | 41 × 431 × 2711 × 143169361 × 2643705155842292927644361<25> × 4464951753212028068412713<25> × 28971751902509263440682681<26> × 896349510145392429932283061091757313213735951<45> × 2517872307605785974471637548714262436055047342788737623015717449321<67> × 8499302998610843705239199741878401678060575277086508852579737810561<67> |