The number of arrangements of 6 identical balls into 3 identical bins is ___.

Question

Accepted Answer

7 When both balls and bins are identical (unlabeled), we are counting unordered partitions of 6 into at most 3 non-negative parts. Bins are indistinguishable, so we list each partition only once, and bins are allowed to be empty. The answer is the number of integer partitions of 6 into at most 3 parts.