Fibonacci number with Scheme

fib.scm

(use srfi-1)

(define (fib n) 
  (let ((alpha (/  (+ 1 (sqrt 5)) 2) )
        (beta  (/  (- 1 (sqrt 5)) 2) )) 

        (round (- (* (/ 1 (sqrt 5)) (expt alpha n)) 
                  (* (/ 1 (sqrt 5)) (expt beta n)))) ))

(print (map (lambda (n) (fib n)) 
            (iota 10 1) ))