Install Prime95 and join the search and discover one of the Mersenne prime numbers. Prime numbers have long fascinated amateur and professional mathematicians. An integer greater than one is called a prime number if its only divisors are one and itself. The first prime numbers are 2, 3, 5, 7, 11, etc. For example, the number 10 is not prime because it is divisible by 2 and 5. A Mersenne prime is a prime of the form 2P-1. The first Mersenne primes are 3, 7, 31, 127 (corresponding to P = 2, 3, 5, 7). There are only 44 known Mersenne primes.
GIMPS, the Great Internet Mersenne Prime Search, was formed in January 1996 to discover new world-record-size Mersenne primes. GIMPS harnesses the power of thousands of small computers like yours to search for these "needles in a haystack".
What is new in this release:
- GIMPS has a new sub-project -- finding (probable) prime Mersenne cofactors.
- Like LL tests, PRP tests now support shift counts to aid in running double-checks.
- PRP tests now support a type of low overhead error checking that almost guarantees correct results even on flaky hardware.
- Because PRP tests are highly reliable, we now offer the option to do PRP tests instead of Lucas-Lehmer primality tests.
- For non-base-2 PRP tests, there is a new option to run each iteration twice and rollback if a mismatch occurs.
What is new in version 29.3:
- Enhanced error checking for LL tests
- Faster step 1 GCD for ECM and P-1 factoring
What is new in version 28.5:
- Changed the output to the worker windows during LL and PRP tests. The new output includes the estimated time to complete the test. There are two new options described in undoc.txt: ClassicOutput and OutputRoundoff.
- Added some new options described in undoc.txt: ScaleOutputFrequency, TitleOutputFrequency, and SilentVictoryPRP.
- Benchmarking on hyperthreaded machines now times only the most common cases. Specifically, hyperthreading is used only in the one cpu and all cpu cases.
- Benchmarking trial factoring is now off by default. Prime95 should not be used for trial factoring. GPUs are about 100 times more efficient at that task.
- On multi-core machines, benchmarks are now run on multiple workers. This measures the effect of memory bandwidth during testing and helps you select the setup that gives you the most throughput.
- There are many new options described in undoc.txt to customize the benchmarking process.