Base 18 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
64: | \[{18^{64}-1\over17}\] | 52 × 13 × 19 × 97 × 113 × 929 × 254209 × 475777 × 113607841 × 3930785153 × 30894471809<11> × 121934274199167596917341199489<30> |