makingchange.fsx

let rec change denominations amount =
    match denominations with
    | [] -> 0
    | _ when amount = 0 -> 1
    | head :: tail when amount < head -> change tail amount
    | head :: tail -> (change denominations (amount - head)) + (change tail amount)
        
change [50; 20; 10; 5; 2; 1] 100;;

makingchange.lisp

(defun make-change (l amount)
    (if l
        (if (= 0 amount)
            1
            (if (< amount (car l))
                (make-change (cdr l) amount)
                (+ (make-change l (- amount (car l)))
                    (make-change (cdr l) amount))))
        0))