Top programs sorted by score
(Another of the Prime Pages' resources)
The Largest Known Primes Icon
  View this page in:   language help
The Prover-Account Top 20
Persons by: number score normalized score
Programs by: number score normalized score
Projects by: number score normalized 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.

1 George Woltman's Prime95 [special] 22 56.9365
2 Jean Penné's LLR [special, plus, minus] 4841 53.7066
3 Geoffrey Reynolds' srsieve [sieve] 3470 53.5070
4 Reynolds and Brazier's PSieve [sieve] 3056 52.8245
5 David Underbakke's AthGFNSieve [sieve] 154 51.6324
6 Yves Gallot's Proth.exe [other, special, plus, minus, classical] 122 51.5003
7 George Woltman's PRP [prp] 56 51.4651
8 Mikael Klasson's Proth_sieve [sieve] 27 51.4459
9 Phil Carmody's 'K' sieves [sieve] 13 51.3970
10 Paul Jobling's SoBSieve [sieve] 6 51.3929
11 Shoichiro Yamada's geneferCUDA [] 7 51.0926
12 OpenPFGW (a.k.a. PrimeForm) [other, sieve, prp, special, plus, minus, classical] 569 51.0510
13 David Underbakke's TwinGen [sieve] 1141 50.7552
14 David Underbakke's GenefX64 [special] 6 50.0884
15 Paul Jobling's NewPGen [sieve] 270 50.0433
16 Yves Gallot's GeneFer [prp, special] 134 49.9699
17 Geoffrey Reynolds' gcwsieve [sieve] 38 49.9336
18 Anand Nair's GFNSvCUDA sieve [sieve] 110 49.8906
19 Mark Rodenkirch's MultiSieve.exe [sieve] 25 49.6778
20 EMsieve [sieve] 28 49.6170


The list above show the programs that are used the most (either by number or score). In some ways this is useless because we are often comparing apples and oranges, that is why the comments in brackets attempt to say what each program does. See the help page for some explanation of these vague categories

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)).