Base 4 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 267: | \[{4^{267}-1\over3}\] | 3 × 7 × 179 × 3739 × 4273 × 62020897 × 78903841 × 28753302853087<14> × 18584774046020617<17> × 618970019642690137449562111<27> × 24124332437713924084267316537353<32> × 7993364465170792998716337691033251350895453313<46> |