Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 419: | \[{4^{419}-1\over3}\] | 839 × 5867 × 903780021613921<15> × 5800422716722833271214743<25> × 548560489336890960473978059<27> × 10287968884341772230096159036619433593<38> × 29919490848598531825060153417921002916701815927<47> × 140218822707485169044055428988288042447908215432246815852158858072198555895717462599488300190371<96> |