second and third extremals of catacondensed hexagonal systems with respect to the pi index
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abstract
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.
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Journal title:
iranian journal of mathematical chemistryPublisher: university of kashan
ISSN 2228-6489
volume 1
issue Issue 1 (Special Issue on the Role of PI Index in Nanotechnology) 2010
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