comparison of topological indices based on iterated ‘sum’ versus ‘product’ operations
نویسندگان
چکیده
the padmakar-ivan (pi) index is a first-generation topological index (ti) based on sums overall edges between numbers of edges closer to one endpoint and numbers of edges closer to theother endpoint. edges at equal distances from the two endpoints are ignored. an analogousdefinition is valid for the wiener index w, with the difference that sums are replaced byproducts. a few other tis are discussed, and comparisons are made between them. the bestcorrelation is observed between indices g and pi; satisfactory correlations exist between w/n3and pi/n2, where n denotes the number of vertices in the hydrogen-depleted graph.
منابع مشابه
Comparison of Topological Indices Based on Iterated ‘Sum’ versus ‘Product’ Operations
The Padmakar-Ivan (PI) index is a first-generation topological index (TI) based on sums over all edges between numbers of edges closer to one endpoint and numbers of edges closer to the other endpoint. Edges at equal distances from the two endpoints are ignored. An analogous definition is valid for the Wiener index W, with the difference that sums are replaced by products. A few other TIs are d...
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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
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