Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
172: | \[{20^{172}-1\over19}\] | 3 × 7 × 173 × 401 × 947 × 2237 × 369122321 × 1887652357 × 2593691596542044913493<22> × 12541974245083294274833711773684280721275134101<47> × 4423036668279780761301352642429727962990898576959823<52> × 10183165864042489505744319341840444146171123988044014091683098589378219601<74> |