Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 389: | \[{4^{389}-1\over3}\] | 56478911 × 4765678679<10> × 1074456464321<13> × 1369379108017267<16> × 2742094407638203<16> × 104172271624747746548384503060864377451510556358244794631358260793846207851<75> × 4684435266636161232578932847604331726884269415306219621279642876954933236537677535849040755779223719<100> |