Go to the primes page, and look for the primes of the form 2 * k *(Mp) + 1 with Mp = Mersenne Prime.
While looking for (prime) possible factors of Double Mersenne numbers, our possible factors increase their sizes with the Mersenne prime exponent.
We are gathering such primes for the most significant exponents.
Go to the Available ranges page, choose a range and the relative software, and click on the "Reserve the range" button. Each range requires less than a week on an average computer run 24/7.
On the new calculation page, you can modify the ranges and your computer's information just overriding the values and clicking on "Input data". When you are satisfied with the values, add your username and click "Send the mail".
It depends on the range, on the software used and on the MMp chosen.
The new page Time calculator will calculate the time required to complete a range with a defined software.
The productivity page shows the k/sec ratio for all programs, and will let you compare different actions for your range.
New status page is shrunk and reports the current work done on each MMp.
New reservations, available ranges, work done pages to get a more focused situation of the search.
New factors view permits to list known factors on a table.
Now it is possible to reserve a range of k for each Double Mersenne number up to MM216049 using either dmdsieve or dmfs
Gary Gostin has released dmfs v0.2, a program that searches for factors of Double Mersenne numbers using multiple cores. The program is CPU-only, and can be found on the Download page.
I will be away from the computer from Nov. 3rd 2025. I'll be back next Nov. 18th.
Happy number crunching!
Mark Rodenkirch releases dmdsieve v1.8.5 and dmdsievecl v1.8.5, an extremely fast sieving program for Linux, MAC and Windows. The new version squashes some bugs and adds speed and reliability
A standalone version of the tester, called dmd_tester as C source code and Windows binary, is available on the download page.
Gary Gostin joined us for double-checking all the results of MM13 to MM28.
While testing his new software, he will push many k limits up. Thanks Gary!
To make sure dmdsieve works fine and there are no holes in the previous tests, we (rogue and ET_) are double-checking all ranges.
After that, we will reopen the reservations for both sieving and testing.
Mark Rodenkirch releases dmdsieve v1.7 and dmdsievecl v1.6, an extremely fast sieving program for Linux, MAC and Windows. In particular, the program dmdsievecl is based on GPU OpenCL code and is pretty fast.
A standalone version of tyhe tester, called dmd_tester as C source code and Windows binary, is available on the download page.
Mark Rodenkirch releases dmdsieve v1.6 and dmdsievecl v1.6, an extremely fast sieving program for Linux, MAC and Windows. In particular, the program dmdsievecl is based on GPU OpenCL code and is pretty fast.
We will soon have a dedicated page with productivity of each software with double Mersenne numbers.
None of the primes found divides MM28
None of the primes found divides the relative double Mersenne number
None of the primes found divides the relative Mersenne number
None of the primes found divides the relative Mersenne number
None of the primes found divides MM32
None of the primes found divides MM31
None of the primes found divides MM30
None of the primes found divides MM29