tasks a-s

This commit is contained in:
Ingy döt Net 2013-04-10 23:57:08 -07:00
parent 47bf37c096
commit b83f433714
12433 changed files with 156208 additions and 123 deletions

View file

@ -0,0 +1,17 @@
(def ! (memoize #(apply * (range 1 (inc %)))))
(defn catalan-numbers-direct []
(map #(/ (! (* 2 %))
(* (! (inc %)) (! %))) (range)))
(def catalan-numbers-recursive
#(->> [1 1] ; [c0 n1]
(iterate (fn [[c n]]
[(* 2 (dec (* 2 n)) (/ (inc n)) c) (inc n)]) ,)
(map first ,)))
user> (take 15 (catalan-numbers-direct))
(1 1 2 5 14 42 132 429 1430 4862 16796 58786 208012 742900 2674440)
user> (take 15 (catalan-numbers-recursive))
(1 1 2 5 14 42 132 429 1430 4862 16796 58786 208012 742900 2674440)