On sharp bounds of the zero-order Randic index of certain unicyclic graphs

نویسندگان

  • Anhua Lin
  • Rong Luo
  • Xiaoya Zha
چکیده

Let G be a simple connected graph and t be a given real number. The zero-order general Randić index αt(G) of G is defined as ∑ v∈V (G) d(v) t , where d(v) denotes the degree of v. In this paper, for any t , we characterize the graphs with the greatest and the smallest αt within two subclasses of connected unicyclic graphs on n vertices, namely, unicyclic graphs with k pendant vertices and unicyclic graphs with a k-cycle. © 2008 Elsevier Ltd. All rights reserved.

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عنوان ژورنال:
  • Appl. Math. Lett.

دوره 22  شماره 

صفحات  -

تاریخ انتشار 2009