Base 15 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
66: | \[{15^{66}-1\over14}\] | 24 × 23 × 67 × 211 × 241 × 463 × 859 × 2333 × 8537 × 3055718821 × 23504771357<11> × 62475406423<11> × 135088596919<12> × 4969143820807<13> |