(The latest computation (pi(10^{23})) revealed a problem in the pix.exe program which has not been solved yet. A difference of 1 exists in the global check. Internal checks were extensively used but did not permit to locate the problem. After months trying to solve this problem, I finally decided to stop the project. I'll be back one day so that the world record pi(x) computation with the pi(x) project will continue.)
The pi(x) computation project is a distributed computation of pi(x) on the web for very large values of x. (Remember that pi(x) is defined as the number of prime numbers less than a given value x, see counting the number of primes). You can contribute to this project provided you have a Pentium (or equivalent chip) machine on Windows. Each computation in the pi(x) project includes the verification.
Counting the number of primes : a page about the history of the subject.
Computation of pi(x) : improvements to the Meissel, Lehmer, Lagarias, Miller, Odlyzko, Deléglise and Rivat method : a preprint describing the algorithm used to compute pi(x) in the pi(x) project.
The pi(x) project mailing list . Be informed of the lastest news on pi(x) computation project (results and new computation) : send a message to xgourdon@yahoo.fr .
The pi(x) table project. This new project, started on April 15 of 2002, aims at computing a large number of values of pi(x) for very large values of x, in order to study the behavior of the pi(x) function in large ranges. And why not, you could find the first known change of sign of the function pi(x)-Li(x) !
numbers, constants and computation