A255943 Number of collections of nonempty multisets with a total of n objects of exactly three colors.

5, 33, 141, 492, 1518, 4320, 11567, 29601, 72981, 174652, 407367, 929859, 2082284, 4585752, 9947997, 21290967, 45007311, 94072878, 194580977, 398589723, 809124321, 1628620153, 3252021750, 6444843618, 12681419489, 24784331646, 48126098418, 92876836752