Base 18 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 75: | \[{18^{75}-1\over17}\] | 73 × 31 × 41 × 151 × 601 × 2711 × 558721 × 602401 × 106487551 × 78180455401<11> × 21162386787273369601<20> × 129278406971133461403718040401<30> |