Called M77232917, the number discovered by Jonathan Pace, a Fedex employee is not only the largest prime number existing, but it is also the 50th first_number of Mersenne, i. e. a prime number that has the form 2p-1. The number represented by 277,232,917-1 has 23,249,425 digits, a colossal number that did not come out of the supercomputer algorithms of a university research center, but from a PC all that is most banal. In fact, in addition to his job at FedEx, Johathan Pace is a system administrator for several associations and it is on one of the machines he manages that he has installed GIMPS, an Open Source software dedicated to this search for Mersenne numbers and that anyone can install to launch this endless quest.
14 years to get the right number!
This is the result of 14 years of research for Jonathan Pace, a former mathematical engineer from Germantown, Tennessee. 14 years to run behind the prizes offered to users of the GIMPS software (for “Great Internet Mersenne Prime Search”). This one announces 182,564 users, sees an installed capacity of about 300 TFLOP/s, 3 times more than the most powerful supercomputers currently in production, the Chinese Sunway TaihuLight which has 10,649,600 computing cores to reach 93 TFLOP/s.
However, when we look at the machine that used Jonathan Pace, it is only a very common PC with an Intel i5-660 that had to run 6 days in a row to verify that M77232917 is a prime number of Mersenne. Similarly, the 4 machines used to check this result show the diversity of software and machines used by members of the GIMPS community. Aaron Blosser used Prime95 software on an Intel Xeon server and was able to obtain the proof in 37 hours of calculation. David Stanfill used an AMD RX Vega 64 graphics card that delivered the result in 34 hours with the gpuOwl software, while Andreas Höglung bet on an NVidia Titan Black card and CUDALucas software that delivered its verdict in 73 hours. The researcher also used Mlucas on a Cloud Amazon Web Services instance that allowed him to get the same result in 65 hours. Finally, Ernest Mayer preferred an Intel Xeon server with 32 cores and the Mlucas software, which allowed him to obtain the proof after 82 hours of calculation.
Thanks to M77232917, Jonathan Pace wins the $3,000 in prizes offered by the EFF, probably a tiny fraction of what he could have earned by mining Bitcoin from the outset, but at least he will have the pleasure of seeing his name among the number one discoverers.
“FedEx employee from Tennessee discovers largest known prime number”, CNBC, 5 January 2018
“Largest known prime number discovered”, ScienceDaily, 4 January 2018
Translated with www.DeepL.com/Translator