Base 31 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
142: | \[{31^{142}-1\over30}\] | 25 × 17609 × 10603709 × 611127785361198601<18> × 642443809919609072204778169817<30> × 1331988009281919919112231122509158475284430963251<49> × 17044025208138339182053051680653494363141751397889<50> × 37141302977105581064921322418772202338727337015016057<53> |