Double Mersennes Prime Search



The Deep Sieving subproject updated its tables.
Each double Mersennes from MM34 to MM48 has its K presieved. Every K under 2,000,000 has been tested.

Aketilander posted the first primality test for a factor of MM48!

Serge Batalov found a titanic prime of more than 909,000 digits while chasing for factors of double Mersenne numbers.

Serge Batalov donated a new powerful PARI script to presieve large groups of Ks faster.
Thank you Serge!

Project DoubleMersennes started gathering the lists of prime factors found while testing double Mesennes possible factors.

LaurV extended the limit of K with status unknown for many double Mersenne numbers.

Serge Batalov scrolled down MM34 and MM35; Deep sieving project starts its chase for Top 5000 primes.

48th Mersenne prime number discovered!
On January 25th at 23:30:26 UTC, the largest known prime number, 257,885,161-1,
was discovered on Great Internet Mersenne Prime Search (GIMPS) volunteer Curtis Cooper's computer.
The new prime number, 2 multiplied by itself 57,885,161 times, less one, has 17,425,170 digits.

New release of mmff!
George Woltman released mmff v0.27.
- Bug in testing 187-bit factors of MM127 fixed.
- -lm makefile bug fixed
- With Batalov's help, the next set of 32 n values in k*2^n+1 Fermat factor testing is available (N<175)
As always previous savefiles wiln not work with 0.27 unless the -nocheck argument is used.


Tony Forbes worked on MM(34) and MM(35) in 2005.
He sieved all k < 500,000 up to 20,000,000,000.
His work has been recorded and is ready to appear on Thank yoy Tony!

A logo contest to embellish the logo of our project has been launched in the appropriate thread of MersenneForum.

Today a new "News" page has been added to the site

A bug in the number_format() function of PHP has been corrected.

Released mmff version 0.26.
- MM31 is now supported.
- The "missing k" range output bug is probably fixed.

mmff_gfn, a software to search for GFN based on mmff kernel is under development.
Thank you Serge Batalov!

Released mmff version 0.25.
- The problem reported with auto-select GPUSievePrimes is fixed.
- The "exponentiation failure" bug where a tested k value is too small for the bit-level being worked on is fixed.
- Exponentiation failures from testing k values that are too large should be fixed.
- The funny %g outputs are gone.
- Removed parts of mfaktc code.

A new subproject has started.
We are searching for the biggest prime number that will not be a Mersenne number, trying to find a prime factor that divides MM47.
The name of the project is still unknown... Any ideas?

Although composite, MM31 has been added to the list of the exponents searched by the project.

A new Factors found page has been added to the site.

Released mmff version 0.24.
- Fixed bug in calculating which Fermat number is divisible by a found factor.
- If GPUSievePrimes is not set in mmff.ini, then mmff chooses a default value based on each entry in worktodo.txt.
- The -st and -st2 mfaktc command line arguments (self-test) are now ignored.
- Some uninitialized mfaktc CPU sieving pointers are no longer freed at exit.

© MoreWare 2012