That is, given a list of distinct positive integer values (representing coin denominations) along with a desired sum, find all minimal bags of coins of the given denominations whose values add up to the desired sum. (N.B., "bag" means that repetition of elements is possible, but order is not significant.)
Examples:
([], 1) => []
([1 2 3], 6) => [[3 3]]
([2 4 6], 7) => []
([11 9 7 5 1], 15) => [[5 5 5] [1 7 7] [1 5 9]]
([11 9 7 5 1], 25) => [[7 9 9] [7 7 11] [5 9 11]]
([11 9 7 5 1], 45) => [[9 9 9 9 9] [7 9 9 9 11] [7 7 9 11 11]
[5 9 9 11 11] [5 7 11 11 11] [1 11 11 11 11]]