There are 5 possible groupings: 0 0 5 - 1 0 1 4 - 5 0 2 3 - 10 1 1 3 - 10 1 2 2 - 20
For a total of 46 possibilities. I don't see a more general formula for this. Because [A][B][C] and [B][A][C] are same, the boxes are indistinguishable that proves.
As a result, 5 orders to indicate 5 indistinguishable objects into 3 indistinguishable boxes.
