Base 21 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 320: | \[{21^{320}-1\over20}\] | 26 × 5 × 11 × 13 × 17 × 41 × 241 × 1217 × 2689 × 9521 × 31873 × 35201 × 40841 × 51521 × 60161 × 62897 × 97241 × 185641 × 300673 × 3441241 × 22995281 × 33534961 × 920421641 × 3184193681 × 6857635489<10> × 363230092241<12> × 415710882920521<15> × 742519225358081<15> × 1023263388750334684164671319051311082339521<43> × 160240451081797786982584096011519912592914325275939917098602236161<66> × 5659400066001744812371391161347769659744650976364564627878379657229417069791676288002909353578404883142904109780249995489289306587234660609146182712711240273601<160> |