Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 51: | \[{20^{51}-1\over19}\] | 421 × 3061 × 60589 × 689852631578947368421<21> × 2200293635138152581356053802893789<34> |
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 51: | \[{20^{51}-1\over19}\] | 421 × 3061 × 60589 × 689852631578947368421<21> × 2200293635138152581356053802893789<34> |