#150 / Palindromic Numbers

[aaron]

Below is my first pass to problem #150, which seems to cause 4clojure to hang. My solution runs quite fast on my local machine, is 4clojure down? Or suffering performance problems? Or is something about my solution wrong? Thanks for any help!

(fn [n]
  (letfn [(pal->num [pal]
            (reduce-kv #(+ %1 (* (int (Math/pow 10 %2)) %3)) 0 (vec pal)))
          (pals [w i]
            (cond
              (= 1 w) (map list (range i 10))
              (= 2 w) (map #(list % %) (range i 10))
              :else (let [sub (pals (- w 2) 0)]
                      (mapcat
                        (fn [n] (map #(concat (list n) % (list n)) sub))
                        (range i 10)))))]
    (let [s (str n)
          w (count s)]
      (filter #(>= % n)
        (cons 0
          (map pal->num (mapcat #(pals % 1) (iterate inc w))))))))

[aaron]

For future reference, this prior answer solved this problem for me:

https://groups.google.com/d/msg/4clojure/vTVF3tCzOGo/123FhNXrzkAJ