Re: A simple sieve in Phobos?

[Kelet]

I've had good luck with Stephan Brumme's block-wise sieve[1], 
also based on the Sieve of Eratosthenes. It's best when 
calculating several blocks in parallel, of course. But it's still 
pretty fast even when used sequentially.

[1]: http://create.stephan-brumme.com/eratosthenes/