This is the same as asking how many different combinations (i.e. the order of the
selection does not matter) can you have if you select k = 100 items with replacement from a
bag containing n = 6 distinct items.
Think of having a total of 100 slots for the jelly beans. The jelly beans are placed in these
100 slots in order of their color, so that we first have all the red ones (if any), then all the
orange ones (if any) and so on. We also place 5 markers to separate jelly beans of different
colors. This gives us a total of 105 possible slots for the jelly beans and the markers.
Each placement of the markers gives a unique distribution of colors. Two markers next to
each other would mean that we do not have any beans of that particular color. E.g. The
distribution above (56 red, 22 yellow and 22 green) would be represented by markers at slots
number 57, 58, 81, 104 and 105.