Top person sorted by score

At this site we keep several lists of primes, most notably the list of the 5,000 largest known primes. Who found the most of these record primes? We keep separate counts for persons, projects and programs. To see these lists click on 'number' to the right.

Clearly one 100,000,000 digit prime is much harder to discover than quite a few 100,000 digit primes. Based on the usual estimates we score the top persons, provers and projects by adding ‎(log n)³ log log n‎ for each of their primes n. Click on 'score' to see these lists.

Finally, to make sense of the score values, we normalize them by dividing by the current score of the 5000th prime. See these by clicking on 'normalized score' in the table on the right.

rank person primes score 781 Pete D'Amico 1 46.7247 782 Jonathan Pritchard 1 46.7203 783 Devlin Skahill 1 46.7186 784 Vaclav Koci 1 46.7163 785 Rick Channing 1 46.7151 786 William Darney 1 46.7150 787 Bastian Gauch 1 46.7110 788 James Wypych 1 46.7093 789 Ed Dugger 1 46.7080 790 Eugeny Mamonov 1 46.7068 791 Ardo van Rangelrooij 1 46.7050 792 Dave Gardner 1 46.7046 793 Dario Canossi 1 46.7011 794 John Christy 1 46.7004 795 Douglas B. McKay 1 46.6983 796 Klaus Gundermann 1 46.6958 797 Rolf Henrik Nilsson 1 46.6957 798 Matthias Baur 5 46.6951 799 Fabio Moreira 1 46.6918 800 Motohiro Ohno 1 46.6907

move up list ↑

move down list ↓

Notes:

Score for Primes

To find the score for a person, program or project's primes, we give each prime n the score (log n)³ log log n; and then find the sum of the scores of their primes. For persons (and for projects), if three go together to find the prime, each gets one-third of the score. Finally we take the log of the resulting sum to narrow the range of the resulting scores. (Throughout this page log is the natural logarithm.)

How did we settle on (log n)³ log log n? For most of the primes on the list the primality testing algorithms take roughly O(log(n)) steps where the steps each take a set number of multiplications. FFT multiplications take about

O( log n ^. log log n ^. log log log n )

operations. However, for practical purposes the O(log log log n) is a constant for this range number (it is the precision of numbers used during the FFT, 64 bits suffices for numbers under about 2,000,000 digits).

Next, by the prime number theorem, the number of integers we must test before finding a prime the size of n is O(log n) (only the constant is effected by prescreening using trial division).  So to get a rough estimate of the amount of time to find a prime the size of n, we just multiply these together and we get

O( (log n)³ log log n ).

Finally, for convenience when we add these scores, we take the log of the result.  This is because log n is roughly 2.3 times the number of digits in the prime n, so (log n)³ is quite large for many of the primes on the list. (The number of decimal digits in n is floor((log n)/(log 10)+1)).