On Tue, Dec 11, 2012 at 5:11 PM, Stephen Bloch <sbl...@adelphi.edu> wrote:


> How many primes are below ten million?  A hundred million?  At some point 
> storing the primes will take less memory than storing primality flags, but 
> that point may be above the size of tables we can realistically store today.

> (for ((i (in-range 3 9)))
    (printf "~a: ~a~n" i (boolean-vector-count (boolean-sieve (expt 10 i)))))
3: 168
4: 1229
5: 9592
6: 78498
7: 664579
8: 5761455

(some values may be higher than the right number, as my boolean-sieve
function rounds up the limit to the next 8 multiple)

P.
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