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# Sierpiński-Riesel Base 5

The **Sierpiński-Riesel Base 5 Project** is a distributed computing project. It was formerly managed by users of mersenneforum.org, and is currently a subproject on PrimeGrid.

## Goal

Sierpiński-Riesel Base 5 tries to prove that `k`=159986 is the smallest possible Sierpiński number base 5 and that `k`=346802 is the smallest possible Riesel number base 5. To prove this, one must find primes for all `k` below the smallest known number.

## How to participate

Participants in either of the projects reserve a `k` in the forum, then use NewPGen to sieve and then LLR to PRP test (for primality). After that, users unreserve their `k` again if no primes are found. Instructions to the project can be found at OmbooHankvalds guidepages.

## Status

The correct countings are shown only if every `k`-value has its own page.

- PrimeGrid Riesel base 5: There are
**53**values to prove. - PrimeGrid Sierpiński base 5: There are
**29**values to prove.