Tiago Carvalho wrote:
<snip>
I've done this a while ago. But if I remember correctly you only need to
verify 2, 3, and after that all primes will be forms of 6k+1 or 6k-1.
This made my code a lot faster at the time.
Don't know if this is faster in this case since you have to store values
in an array (or other storage), but if you store the calculated primes,
you only need to test the current value against those.
See my reply to Michael. My fast prime finder keeps an array of primes,
and maintains a slice of this array up to the square root of the number
being tested.
If a umber can't
be divided by none of the primes below it, it's prime.
No, if it can't be divided by _any_ of the primes below it, it's prime.
Stewart.
