Some signed graphs whose eigenvalues are main
نویسندگان
چکیده
• Let G be a graph. For subset X of V ( ), the switching σ is signed graph obtained from by reversing signs all edges between and ) ∖ . A( adjacency matrix An eigenvalue called main if it has an eigenvector sum whose entries not equal to zero. Two equivalent graphs share same spectrum, while they may have different eigenvalues. Akbari et al. (2021) conjectured that let ≠ K 2 , 4 { e } Then there exists such eigenvalues are main. S n k complete − r attaching pendent at some vertex In this paper we prove when multipartite graph, or harmonic tree, These results partly confirm conjecture A
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ژورنال
عنوان ژورنال: Applied Mathematics and Computation
سال: 2022
ISSN: ['1873-5649', '0096-3003']
DOI: https://doi.org/10.1016/j.amc.2022.127014