On Fri, 5 Sep 2014 16:35:18 -0600, Ian Kelly <ian.g.ke...@gmail.com> wrote:
>On Fri, Sep 5, 2014 at 3:49 PM, Seymore4Head ><Seymore4Head@hotmail.invalid> wrote: >> I am sure this has already been done, but after it was pointed out >> that you don't need to test for any number that multiplies by 2 it >> made me think again. >> >> If you start with the list [3,5,7] and step through the list of all >> remaining odd numbers (step 2), and start appending numbers that won't >> divide by numbers already appended in the list, that would seem like a >> pretty efficient way to find all prime numbers. > >Indeed, this type of algorithm is known as a sieve. For a (literally) >classical example, see >http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes > >It's a nice way to find all the prime numbers up to a given limit, or >it can be modified to run indefinitely high, but it's not very >efficient for determining the primality of a single number. That is a pretty nice example. Thanks -- https://mail.python.org/mailman/listinfo/python-list
