fibonacci with elisp

fib1.el

(defun fib (n)
  (fib-iter 1 0 n))

(defun fib-iter (a b count)
  (if (= count 0)
      b
    (fib-iter (+ a b) a (- count 1))))

fib2.el

(defun fib (n)
  (cond ((= n 0) 0)
	((= n 1) 1)
	(t (+ (fib (- n 1))
	      (fib (- n 2))))))

(fib 4)					; => 3
(fib 5)					; => 5
(fib 6)					; => 8
(fib 7)					; => 13