number_of_nonisomorphic_trees

number_of_nonisomorphic_trees(order)

Returns the number of nonisomorphic trees of the specified order.

Based on an algorithm by Alois P. Heinz in OEIS entry A000055. Complexity is O(n ** 3).

Parameters:

orderint

Order of the desired tree(s).

Returns:

int

Number of nonisomorphic trees with order number of nodes.

Raises:

ValueError

If order is negative.

See also

nonisomorphic_trees

Examples

>>> nx.number_of_nonisomorphic_trees(10)
106