Written a Clojure lazy-seq function to generate n prime numbers. It generates .5 million prime numbers in 20 secs

n-primes.clj

;; Clojure lazy-seq function to generate n prime numbers. 
;; It generates .5 million prime numbers in 20 secs using
;; the naive non-sieve algo
;; Author: Abhishek Gupta (@abhilater)

(defn n-primes
  []
  (filter (fn [num]
            (loop [end (int (Math/sqrt num)), div 2, re (rem num div)]
              (cond
                (< num 2) false
                (= num 2) true
                (= re 0) false
                (> div end) true
                :else (recur end (inc div) (rem num div)))
              )) (range)))

;;; (take 500000 (n-primes))