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Finding World Record Primes Since 1996

GIMPS History

Since its founding in 1996, GIMPS has discovered 17 Mersenne primes so far. Could you be next?

For a full history of GIMPS, please see the Wikipedia entry
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GIMPS was founded in 1996 by George Woltman. The software ran on Intel i386 systems using hand-tuned assembly code for the critical calculations, resulting in highly optimized Lucas-Lehmer code.

It wasn't long before GIMPS had it's first discovery in November of that same year, showing the effectiveness of distributed computing in harnessing spare computer cycles in a coordinated effort.

As efficient as the software itself was, the early years of GIMPS involved a manual process using emails to request work assignments and then send the results back. As the project grew, a more efficient system was needed and Scott Kurowski responded to that need with the introduction of PrimeNet through his company Entropia, a pioneer in the early days of distributed computing projects. Without Scott's invaluable contribution, the ability to manage thousands of volunteers and millions of work assignments would not have been possible. PrimeNet paved the way for the future growth of the project as a whole.

With the solid foundation of PrimeNet in place, George continued his focus on improving the core calculations of Prime95. As new Intel and AMD processors were introduced, George worked with the new instruction sets and timings to increase the performance. The core of the program is now able to optimize itself to work at peak efficiency on all modern CPU's, but also still finds a home on many older generation systems.

To see a list of all the large and small milestones in the GIMPS project, please see this page: GIMPS Milestones

Discovered Primes

  1. 1996-11-13 – Joel Armengaud discovered the 35th known Mersenne prime, 21398269-1
  2. 1997-08-24 – Gordon Spence discovered the 36th known Mersenne prime, 22976221-1
  3. 1998-01-27 – Roland Clarkson discovered the 37th known Mersenne prime, 23021377-1
  4. 1999-06-01 – Nayan Hajratwala discovered the 38th known Mersenne prime, 26972593-1
  5. 2001-11-14 – Michael Cameron discovered the 39th known Mersenne prime, 213466917-1
  6. 2003-11-17 – Michael Shafer discovered the 40th known Mersenne prime, 220996011-1
  7. 2004-05-15 – Josh Findley discovered the 41st known Mersenne prime, 224036583-1
  8. 2005-02-18 – Dr. Martin Nowak discovered the 42nd known Mersenne prime, 225964951-1
  9. 2005-12-15 – Curtis Cooper and Steven Boone discovered the 43rd known Mersenne prime, 230402457-1
  10. 2006-09-04 – Curtis Cooper and Steven Boone discovered the 44th known Mersenne prime, 232582657-1
  11. 2008-09-06 – Hans-Michael Elvenich discovered the 45th known Mersenne prime, 237156667-1
  12. 2009-06-04 – Odd Magnar Strindmo discovered the 46th known Mersenne prime, 242643801-1
  13. 2008-08-23 – Edson Smith discovered the 47th known Mersenne prime, 243112609-1
  14. 2013-01-25 – Curtis Cooper discovered the 48th known Mersenne prime, 257885161-1
  15. 2016-01-07 – Curtis Cooper discovered the 49th known Mersenne prime, 274207281-1
  16. 2017-12-26 – Jonathan Pace discovered the 50th known Mersenne prime, 277232917-1
  17. 2018-12-07 – Patrick Laroche discovered the 51st known Mersenne prime, 282589933-1


Newsletters detailing some of the early history of GIMPS are available. Newsletters are dated: