Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 373: | \[{4^{373}-1\over3}\] | 60427 × 25569151 × 694579497316894264425661243659806371972188318857<48> × 152796756325290043462779779478758328705905947521327614399129<60> × 752440346497356983142327449546457327748644897934114291899411428982990336039662496766303354959577078458241<105> |