Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 285: | \[{4^{285}-1\over3}\] | 3 × 7 × 11 × 31 × 151 × 191 × 331 × 571 × 2281 × 32377 × 174763 × 524287 × 1101811 × 1212847 × 160465489 × 420778751 × 30327152671<11> × 3011347479614249131<19> × 1491477035689218775711<22> × 25349242986637720573561<23> × 15653990705896313547269237220041169361<38> |