On the Estrada Index of Point Attaching Strict $k$-Quasi Tree Graphs
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Authors: M. A. IRANMANESH AND R. NEJATI
DOI: 10.46793/KgJMat2002.165I
Abstract:
Let G = (V,E) be a finite and simple graph with λ1,λ2,…,λn as its eigenvalues. The Estrada index of G is EE(G) = ∑ i=1neλi. For a positive integer k, a connected graph G is called strict k-quasi tree if there exists a set U of vertices of size k such that G ∖ U is a tree and this is as small as possible with this property. In this paper, we define point attaching strict k-quasi tree graphs and obtain the graph with minimum Estrada index among point attaching strict k-quasi tree graphs with k even cycles.
Keywords:
Estrada Index, quasi tree graph, point attaching Strict k-quasi tree graph.
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