Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
307: | \[{3^{307}-1\over2}\] | 10610542242923144869<20> × 1209358403350153553775181<25> × 11665479581585055349598973071696589607991946673408334574649356416413027107729461307877711679909644074637<104> |