Euler 3, JS and Clj

// First attempt - errors on x<2
// with 1 param
var largestprimefactor = function (x) {
  return (function recur(v, d) {
    if (v === d) return v;
    if (v % d === 0) return recur(v / d, d);
    return recur(v, d + 1);
  }(x, 2));
};
// with two params
var largestprimefactor = function recur(x, d) {
  if (v === d) return v;
  if (v % d === 0) return recur(v / d, d);
  return recur(v, d + 1);
};

// Second attempt - Seems to work fine!
var largestprimefactor = function (_num) {
  var num = Math.abs(_num);
  if (num < 2) return num;
  return (function recur(v, d) {
    if (v === d) return v;
    if (v % d === 0) return recur(v / d, d);
    if (d === 2) return recur(v, 3);
    return recur(v, d + 2);
  }(num, 2));
};

; Clojure version of second attempt
(defn largestprimefactor [_num]
  (let [num (Math/abs _num)]
    (if (< num 2) num)
    (loop [v num d 2]
      (cond
        (= v d) v
        (= 0 (mod v d)) (recur (/ v d) d)
        (= d 2) (recur v 3)
        :else (recur v (+ 2 d))))))