P39

# Sieve of Eratosthenes
(de primes (A B)
   (let Sieve (range 1 B)
      (set Sieve)
      (for I (cdr Sieve)
         (when I
            (for (S (nth Sieve (* I I)) S (nth (cdr S) I))
               (set S) ) ) )
      (filter '((N) (>= N A)) Sieve) ) )

http://picolisp.com/wiki/?99p39

10jul10

abu