rosettacode.org/wiki/McNuggets_problem

Calculate (from 0 up to a limit of 100) the largest
non-McNuggets number (a number n which cannot be expressed
with 6x + 9y + 20z = n where x, y and z are natural numbers).

Output:

43


newLISP

(define (cartesian-product lists)
(if (null? lists)
'(())
(let (subproduct (cartesian-product (rest lists)))
(apply append
(map
(fn (x) (map (fn (xs) (cons x xs)) subproduct))
(first lists))))))

(define (nug? x)
(let (top 100)
(exists
(fn (combo) (= x (apply + combo)))
(cartesian-product
(list (sequence 0 top 6)
(sequence 0 top 9)
(sequence 0 top 20))))))

(exists (fn (n) (not (nug? n))) (sequence 100 0))
===>
43

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)