Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 308: | \[{4^{308}-1\over3}\] | 5 × 17 × 23 × 29 × 43 × 89 × 113 × 127 × 353 × 397 × 617 × 683 × 2113 × 8317 × 13553 × 78233 × 15790321 × 869467061 × 2931542417 × 3019242689 × 35532364099<11> × 74153335873<11> × 76096559910757<14> × 581283643249112959<18> × 1867935023317328048519811865525337712653538206737478396129<58> |