Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
263: | \[{3^{263}-1\over2}\] | 53653 × 78901 × 2750510656513<13> × 65397307474141<14> × 153572905037740933<18> × 352436749324038579121<21> × 3688200234744568182050401066389522755138234431221709<52> |