Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 75: | \[{20^{75}-1\over19}\] | 11 × 31 × 61 × 151 × 251 × 421 × 1451 × 3001 × 11251 × 261451 × 1369801 × 7466201 × 46794901 × 9308203137060768572251<22> × 104988737576990732806404001<27> |