Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
89: | \[{20^{89}-1\over19}\] | 179 × 335939325419<12> × 1547547240361<13> × 133724350874825473368329<24> × 261786786940548104294757775699593263493783883864102345432362297509<66> |