Prime Summands

prime_summands.clj

(ns prime-summands.core
  (:use [clojure.contrib.lazy-seqs :only #{primes}]))

(defn prime-summands [n]
  (let [primes (take-while #(<= % n) primes)]
    (reduce +
            (for [start (range (count primes))]
              (let [primes-sums (->> primes
                                     (drop start)
                                     (reductions +)
                                     (take-while #(<= % n)))]
                (if (some #{n} primes-sums)
                  1 0))))))