Base 18 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
89: | \[{18^{89}-1\over17}\] | 2671 × 1412957489047649<16> × 36037321554594103<17> × 2373467556415439369<19> × 17280008471529631881887<23> × 55248602049369094679202144729777041<35> |