September 2017 Update

Task/Amicable-pairs/Clojure/amicable-pairs.clj

@@ -0,0 +1,23 @@
+(ns example
+  (:gen-class))
+
+(defn factors [n]
+  " Find the proper factors of a number "
+  (into (sorted-set)
+        (mapcat (fn [x] (if (= x 1) [x] [x (/ n x)]))
+                (filter #(zero? (rem n %)) (range 1 (inc (Math/sqrt n)))) )))
+
+
+(def find-pairs (into #{}
+               (for [n (range  2 20000)
+                  :let [f (factors n)     ; Factors of n
+                        M (apply + f)     ; Sum of factors
+                        g (factors M)     ; Factors of sum
+                        N (apply + g)]    ; Sum of Factors of sum
+                  :when (= n N)           ; (sum(proDivs(N)) = M and sum(propDivs(M)) = N
+                  :when (not= M N)]       ; N not-equal M
+                 (sorted-set n M))))      ; Found pair
+
+;; Output Results
+(doseq [q find-pairs]
+  (println q))