The Inertia Indexes of One Special Kind of Tricyclic Graphs
- 1 Department of Mathematics, Qinghai University for Nationalities Xining, Qinghai, China
- 2 Department of Mathematics, Qinghai University for Nationalities Xining, Qinghai, China
Abstract
Let G be a graph and A=(a ij ) n ×n be the adjacency matrix of G , the eigenvalue s of A are said to be the eigenvalues of the graph G , and to form the spectrum of this graph. The number s of positive, negative and zero eigenvalues in the spectrum of the graph G are called positive and negative inertia indexes and nullity of the graph G , are denoted by p(G) , n(G), η (G) , respectively, and are collectively called inertia indexes of the graph G . The inertia indexes ha ve many important applications in chemistry and mathematics. The purpose of the research of this paper is to calculat e the inertia indexes of one special kind of tricyclic graphs. A new calculation method of the inertia indexes of this tricyclic graphs with large vertices is given, and the inertia indexes of this tricyclic graphs with fewer vertices can be calculated by Matlab.
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