Primes by sieve of Eratosthenes (lazy evalution)

gistfile1.clj

(defn nums [] (iterate inc 2))

(defn sieve [[p & xs]]
  (remove #(= (rem % p) 0) xs))

(defn primes []
  (map first (iterate sieve (nums))))

;; user> (take 20 (primes))
;; (2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71)