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Operations Research Transactions >

2024 , Vol. 28 >Issue 4: 152 - 161

DOI: https://doi.org/10.15960/j.cnki.issn.1007-6093.2024.04.015

Mixed graphs with negative inertia index 1

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  • 1. School of Mathematical Sciences, Anhui University, Hefei 230601, Anhui, China

Received date: 2022-08-18

  Online published: 2024-12-20

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, 2024, All rights reserved, without authorization
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Abstract

A mixed graph is obtained by orienting some edges of a simple graph. The negative inertia index of a mixed graph is defined as the number of negative eigenvalues of its adjacency matrix. This paper mainly studies the negative inertia index of mixed graphs via the second kind Hermitian adjacency matrix. All mixed graphs with negative inertia index 1 are characterized.

Key words： mixed graph; negative inertia index; twin vertices; reduced graph

Cite this article

Ziyan CHEN, Yun QIAO, Yi WANG . Mixed graphs with negative inertia index 1[J]. Operations Research Transactions, 2024 , 28(4) : 152 -161 . DOI: 10.15960/j.cnki.issn.1007-6093.2024.04.015

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