(define (cont-frac-rec n d k)
  (define (rec i)
    (if (= i k)
      (/ (n i) (d i))
      (/ (n i) 
	(+ (d i) (rec (+ i 1))))))
  (rec 1))

(define (cont-frac-iter n d k)
  (define (iter i res)
    (if (= i 0)
      res
      (iter (- i 1)
	(/ (n i) (+ res (d i))))))
  (iter k 0))


(define phi (/ (+ 1 (sqrt 5)) 2))

; 10 iterations needed to approximate phi using 
; (lambda (i) 1.0) for n and d.