Base 20 Repunits
Table
Format: small prime × proven prime<size> × (probable prime)<size> × [composite]<size> × {unknown}<size>
| 400: | \[{20^{400}-1\over19}\] | 3 × 7 × 11 × 17 × 41 × 61 × 101 × 151 × 251 × 401 × 1451 × 1601 × 2801 × 25601 × 76001 × 148721 × 152381 × 160001 × 222361 × 1369801 × 7466201 × 46794901 × 1505882353 × 3767298565601<13> × 32018865275041<14> × 4406613081041681<16> × 10960869459557201<17> × 36070095715550228401<20> × 176495898629033039186561<24> × 1038193734970398415809901<25> × 10995116277758926258176000104857599999989760000000001<53> × 305778786555423393243840359420104066007516066275385539831224653094401<69> × 44939840823522456170286865824642668270634223087269485278608534401567146380946777601<83> × 2106150854754356494349220643514129289660396393371942676169713029706197959011862755149480537274846644229601<106> |