second and third extremals of catacondensed hexagonal systems with respect to the pi index
نویسندگان
چکیده
the padmakar-ivan (pi) index is a wiener-szeged-like topological index which reflectscertain structural features of organic molecules. the pi index of a graph g is the sum of alledges uv of g of the number of edges which are not equidistant from the vertices u and v. inthis paper we obtain the second and third extremals of catacondensed hexagonal systems withrespect to the pi index.
منابع مشابه
Second and Third Extremals of Catacondensed Hexagonal Systems with Respect to the PI Index
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:
iranian journal of mathematical chemistryناشر: university of kashan
ISSN 2228-6489
دوره 1
شماره Issue 1 (Special Issue on the Role of PI Index in Nanotechnology) 2010
کلمات کلیدی
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