The fastest know algorithm to compute factorials uses the prime factors of the factorial. This can be done quite easily but needs a list of primes to do so. One of the simplest way to do it—and a quite fast way—is the old algorithm invented by a greek guy named Eratosthenes of Cyrene. OK, he was greek, so he wrote his name most probably Ἐρατοσθένης.
We are not really interrested in the literacy of ancient greeks but in their inventions. and Eratosthenes invented a lot One of those findings was a prime sieve and it got even named after him!
The picture behind the fold is a closeup of the well fed girl in the header. A very close close-up! Continue reading
A very basic but working big integer implementation
In this episode we will build a basic set of operations, namely addition,
subtraction and multiplication. Division is not needed but will be given,
too, as I am without mercy. Continue reading
Felis silvestris catu (vicinae)
…another picture of a cat.
This is the first post of what will be a very long series about calculating factorials and it is even a long way to the first calculation of a factorial.
available for free and for money, and the author has a lot of that stuff already written. The last argument is the winning one, of course.
Oh, and: yes, this implementation will be with FFT!
A plant this time; flowers for the non-existent commenters.