'Returns the number of nodes in the tree.
Examples
>>> from sympy.combinatorics.prufer import Prufer
>>> Prufer([[0, 3], [1, 3], [2, 3], [3, 4], [4, 5]]).nodes
6
>>> Prufer([1, 0, 0]).nodes
5'

@property
def nodes(self):

    return self._nodes
