Note: Due to changes in the Riesel prime template, most of those pages (and related) are not shown properly.This will take some time! Wanna help? Please move any Riesel prime page first, then edit/add the base parameter. |

**Navigation**

Topics | Register • News • History • How to • Sequences statistics • Template prototypes |

# Riesel number base 5

A **Riesel number base 5** is a value of *k* such that *k × 5 ^{n} - 1* is always a composite number.

Using the same method presented in the Riesel problem article, it was found that *346,802 × 5 ^{n} - 1* is multiple of 3, 7, 13, 31 or 601 (the covering set) depending on the value of n, so it is always composite.

In order to demonstrate whether 346,802 is the smallest Riesel number base 5 or not, a distributed computing project was created named Sierpiński-Riesel Base 5