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On the general sum-connectivity index of trees

✍ Scribed by Zhibin Du; Bo Zhou; Nenad Trinajstić

Publisher
Elsevier Science
Year
2011
Tongue
English
Weight
226 KB
Volume
24
Category
Article
ISSN
0893-9659

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✦ Synopsis

The general sum-connectivity index of a graph G is defined as

, where d u denotes the degree of vertex u in G, E(G) denotes the edge set of G, and α is a real number. We determine the maximum value for the general sum-connectivity indices of n-vertex trees and the corresponding extremal trees for α < α 0 , where α 0 = -4.3586 . . . is the unique root of the equation 4 α -5 α 5 α -6 α = 3.

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