Factorial & Fibonnaci en Clojure

fyf.clj

;; Factorial Recursivo
;; http://stackoverflow.com/questions/1662336/clojure-simple-factorial-causes-stack-overflow
(defn !-recursive [x]
  (if (= x 1) 1N
              (* x (!-recursive (dec x)))))

;; Factorial Iterativo
;; https://mitpress.mit.edu/sicp/full-text/sicp/book/node15.html
(defn !-iterative
  ([x] (!-iterative 1N 1 x))
  ([acc i x] (if (> i x) acc
                         (!-iterative (* i acc) (inc i) x))))

;; Factorial Loop/Recur
;; https://clojuredocs.org/clojure.core/loop
(defn !-loop [x]
  (loop [i x acc 1N]
    (if (= i 1) acc
                (recur (dec i) (* acc i)))))

;; Factorial Reduce
;; http://stackoverflow.com/questions/1662336/clojure-simple-factorial-causes-stack-overflow
(defn !-reduce [x]
  (reduce * (range 1N (inc x))))

;; Fibonacci 1 
;; http://stackoverflow.com/questions/8939970/a-recursive-fibonacci-function-in-clojure
(defn fib1
  ([n] (fib1 [0 1] n))
  ([x, n] (if (>= (count x) n) x
                               (recur (conj x (apply + (take-last 2 x))) n))))

;; Fibonacci 2 
;; http://c2.com/cgi/wiki?FibonacciSequence
(defn fib2[n]
  (loop [m 0 k 1 i n x []]
    (if (= i 0) x
                (recur k (+ m k) (- i 1) (conj x m)))))