Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 374: | \[{4^{374}-1\over3}\] | 5 × 23 × 89 × 137 × 397 × 683 × 953 × 2113 × 5237 × 26317 × 43691 × 131071 × 707983 × 551353793 × 26509131221<11> × 1819762572673<13> × 35155077044989397<17> × 4029292065629191839853<22> × 135322045917118601273437<24> × 1032670816743843860998850056278950666491537<43> × 2191165825376888084750157716424579062015865776131<49> |