Small and Not so Small Equienergetic Graphs
نویسندگان
چکیده
We show that, contrary to the claims of several authors that there exists no equienergetic graphs on seven vertices, there exists 21 sets of noncospectral, equienergetic graphs on seven vertices. We also give the number and cardinality of sets of equienergetic connected graphs on eight, nine and ten vertices, and equienergetic trees and chemical trees on up to 22 vertices. Finally, we construct two new infinite families of equienergetic graphs.
منابع مشابه
Constructing pairs of equienergetic and non-cospectral graphs
The energy of a simple graph G is the sum of the absolute values of the eigenvalues of its adjacency matrix. Two graphs of the same order are said to be equienergetic if they have the same energy. Several ways to construct equienergetic non-cospectral graphs of very large size can be found in the literature. The aim of this work is to construct equienergetic non-cospectral graphs of small size....
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