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

نویسندگان

  • S. MORADI Arak University, Iran
  • Z. YARAHMADI Islamic Azad University, Khorramabad Branch, I. R. Iran
چکیده مقاله:

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.

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عنوان ژورنال

دوره 1  شماره Issue 1 (Special Issue on the Role of PI Index in Nanotechnology)

صفحات  95- 103

تاریخ انتشار 2010-04-01

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