New skew equienergetic oriented graphs

Authors

  • Cunxiang Duan Department of Applied Mathematics, School of Science, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, People's Republic of China
  • Ligong Wang Department of Applied Mathematics, School of Science, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, People's Republic of China.
  • Xiangxiang Liu Department of Applied Mathematics, School of Science, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, People's Republic of China
Abstract:

Let $S(G^{sigma})$ be the skew-adjacency matrix of the oriented graph $G^{sigma}$, which is obtained from a simple undirected graph $G$ by assigning an orientation $sigma$ to each of its edges. The skew energy of an oriented graph $G^{sigma}$ is defined as the sum of absolute values of all eigenvalues of $S(G^{sigma})$. Two oriented graphs are said to be skew equienergetic iftheir skew energies are equal. In this paper, we determine the skew spectra of some new oriented graphs. As applications, we give somenew methods to construct new non-cospectral skew equienergetic oriented graphs.

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Journal title

volume 4  issue 1

pages  15- 24

publication date 2019-06-01

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