Mersenneplustwo factorizations

The Mersenneplustwo factorizations is a project, which tries to factor numbers of the form: 2^p+1 (with p being a prime, as well as simultaneously 2^p-1 being prime). All such numbers are divisible by 3 since 2^p-1 is not divisible by 3 (it's assumed to be prime) and 2^p is not divisible by 3 (it's only prime factor is 2).

It is managed by James Wanless (bearnol).

How to participate

Participants use ECMclient to automatically download numbers, do ECM curves on them and upload them again.

Status

As of this moment (2005-09-12), about 8GHz is being dedicated to this project - more needed! :-)

Results

Best results so far include 37-digit factor of $M_{9941}+2$ (FDBid) found by ECMNet, as well as 36-digit factor of $M_{11213}+2$ (FDBid) found using mprime (the linux version of Prime95 by George Woltman) More recently, a 41-digit factor of $M_{110503}+2$ was also found by ECMNet.

External links

• Official page
• Discussion group
• distributedcomputing.info entry