Some results on the complete sigraphs with exactly three non-negative eigenvalues

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Document Type : Original paper

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Department of Mathematics, Karaj Branch, Islamic Azad University, Karaj, Iran

Abstract

Let $(K_{n},H^-)$ be a complete sigraph of order $n$ whose negative edges induce a subgraph $H$. In this paper, we characterize $(K_n,H^-)$ with exactly 3 non-negative eigenvalues, where $H$ is a non-spanning two-cyclic subgraph of $K_n$.

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References

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Communications in Combinatorics and Optimization

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Available Online from 20 January 2024

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