counting primes




On Wed, 31 Mar 2010, Jean Legeande wrote:

< Dear Maxima users,
< ?
< What is a good way to?code the prime-counting function with Maxima ?
 
How about:

pi[n]:=if n = 2 then 1 elseif primep(n) then pi[n-1]+1 else pi[n-1] ;

I use a hash function so that we only ever need to compute pi[n] once,
for any n.

Leo
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