Abstract
Let t(r, n) be the number of trees with n vertices of which r are hanging and q are internal (r=n−9). For a fixed r or q we prove the validity of the asymptotic formulas (r > 2)t(r, n)≈t/r¦(r−2)¦ 22−r n 2r−4 (n→∞)t(n−q, n)≈1/q¦(q−1)¦q q−2 n q−1 (n→∞) In the derivation of these formulas we do not use the expression for the enumerator of the trees with respect to the number of hanging vertices.
Similar content being viewed by others
Literature cited
R. Otter, “The number of trees,” Ann. Math.,49, 583–599 (1948).
F. Harary and G. Prins, “The number of homeomorphically irreducible trees and other species,” Acta Math.,101, 141–162 (1959).
K. A. Rybnikov, Introduction to Combinatorial Analysis [in Russian], Izd. Mosk. Gos. Univ., Moscow (1972).
N. G. De Bruijn, “The theory of Pólya enumerations,” in: Applied Combinatorial Mathematics [in Russian], Mir, Moscow (1968), pp. 61–106.
J. Riordan, “The enumeration of labelled trees by degrees,” Bull. Am. Math. Soc.,72, 110–112 (1966).
O. Ore, Theory of Graphs, Colloquium Publications Series, Vol. 38, American Mathematical Society (1967).
F. Harary, Graph Theory, Addison-Wesley (1969).
Author information
Authors and Affiliations
Additional information
Translated from Matematicheskie Zametki, Vol. 21, No. 1, pp. 65–70, January, 1977.
Rights and permissions
About this article
Cite this article
Voblyi, V.A. Asymptotic formulas for the enumerator of trees with a given number of hanging or internal vertices. Mathematical Notes of the Academy of Sciences of the USSR 21, 36–39 (1977). https://doi.org/10.1007/BF02317033
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02317033