Abstract
Let G be an irregular graph on n vertices with maximum degree \(\Delta \ge 3\) and diameter \(D\ge 3\). The spectral radius of G, which is denoted by \(\rho (G)\), is the largest eigenvalue of the adjacency matrix of G. In this paper, a new lower bound of \(\Delta -\rho (G)\) is given, which improves the previous bounds intrinsically.
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Feng, R., Zhang, W. A Note on Spectral Radius and Maximum Degree of Irregular Graphs . Graphs and Combinatorics 37, 1121–1127 (2021). https://doi.org/10.1007/s00373-021-02311-y
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DOI: https://doi.org/10.1007/s00373-021-02311-y