Kragujevac J. Math. 27 - 1
Kragujevac J. Math. (2005) 5-9.

MODIFIED WIENER INDICES OF THORN TREES

Bo Zhou

Department of Mathematics, South China Normal University,
Guangzhou 510631, P. R. China (e-mail: zhoubo@scnu.edu.cn)

(Received December 14, 2004)

Abstract. The
l-modified Wiener index ^{m}W_{l} provides a class
of structure-descriptors to measure the branching of the
carbon-atom skeleton molecules. A thorn tree is formed by
attaching some new vertices of degree one to each vertex of the
parent tree. An explicit expression is deduced enabling the
calculation of the k-modified Wiener index of a type of thorn
tree in terms of the i-modified Wiener indices of the parent
tree for any natural number k with 0 £ i £ k.