Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 399: | \[{4^{399}-1\over3}\] | 3 × 72 × 43 × 127 × 337 × 571 × 4523 × 5419 × 32377 × 63841 × 73417 × 83791 × 174763 × 524287 × 1212847 × 160465489 × 11355690325205671380495907537<29> × 106788290443848295284382097033<30> × 109801296198740392094858844294643<33> × 163537220852725398851434325720959<33> × 29724614739876344125010817433703775877960388838436140673<56> |