Labelled tree count with prescribed degrees

ID: labelled-tree-count-with-prescribed-degrees

For and positive integers with , the number of labelled trees having vertex degree at label is
By the Prüfer degree formula, this is the multinomial coefficient counting sequences with occurrences of each label. If a degree is zero or the sum is wrong, there are no such trees. For the example degree sequence , there are labelled trees, one for each ordering of the labels . Knowing the vertex degrees thus constrains, but usually does not determine, the tree.

New to topics? Read the docs here!