Second and Third Extremals of Catacondensed Hexagonal Systems with Respect to the PI Index

نویسندگان
YARAHMADI, Z. ID 1
MORADI, S. ID 2

1 Islamic Azad University, Khorramabad Branch, I. R. Iran

2 Arak University, Iran

doi
10.22052/ijmc.2010.5139
چکیده

The Padmakar-Ivan (PI) index is a Wiener-Szeged-like topological index which reflects certain structural features of organic molecules. The PI index of a graph G is the sum of all edges uv of G of the number of edges which are not equidistant from the vertices u and v. In this paper we obtain the second and third extremals of catacondensed hexagonal systems with respect to the PI index.

کلیدواژه‌ها
topological index, PI index, Catacondensed hexagonal system