Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| * 508: | \[{20^{508}-1\over19}\] | 3 × 7 × 401 × 509 × 18797 × 22861 × 206249 × 419609 × 78732889 × 1806905201 × 2824620209 × 312576217052731918639<21> × 57564425105062873850506481<26> × 9024329685219466934919221249<28> × 2042832095173841227635611678280020546809<40> × 657052369159196348354107943940109671040881828497963263263097769266629401<72> × 62368770429251821715505778874398353534071110029758004648111605459751162054686199377653947028251626418709594155079<113> × [506530757924563311400330051629719606861127989946045615998843459034516162407743368774075696414556056496455271015441001404760400767696783298772545687026578967862519709266927758071572217386508153636608176373193315479489680205331558578650578067181947761191168968055514735659947201182017986261091081725573948072237<309>] |