Base 3 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
241: | \[{3^{241}-1\over2}\] | 553788718707122198751861425724478919<36> × 8746781693759220836960579574321515651597080180989131549946798109975686695403479<79> |