#!/run/current-system/profile/bin/env gxi-script
(define multiple-of-3-or-5
   (lambda (x) (case
                  (or (= 0 (modulo x 3)) (= 0 (modulo x 5)))
                     ((#t) #t)
                     ((#f) #f))))

(define countdown (lambda (x) (if (> x 0)
                                 ((lambda ()
                                    (if (multiple-of-3-or-5 x)
                                       (println x)))))
                                    (if (not (eqv? 2 (- -1 x)))
                                       (countdown (- x 1)))))
(countdown 1000)