Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 44: | \[{20^{44}-1\over19}\] | 3 × 7 × 23 × 89 × 401 × 170770770413<12> × 424016563147<12> × 6881957521693<13> × 10778947368421<14> |