Base 18 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 79: | \[{18^{79}-1\over17}\] | 338279 × 1104737 × 12802037494726063<17> × 9886837665707422272737<22> × 1824771736962009962008821260930608362080770046711<49> |