Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 266: | \[{4^{266}-1\over3}\] | 5 × 29 × 43 × 113 × 127 × 229 × 457 × 1597 × 2129 × 4523 × 174763 × 524287 × 525313 × 126848469231149<15> × 679253585011429<15> × 106788290443848295284382097033<30> × 449329386292232535250647435097<30> × 163537220852725398851434325720959<33> |