The $ \epsilon $-spectral radius of a connected graph is the largest eigenvalue of its eccentricity matrix. In this paper, we identify the unique $ n $-vertex tree with diameter $ 4 $ and matching number $ 5 $ that minimizes the $ \epsilon $-spectral radius, and thus resolve a conjecture proposed in [W. Wei, S. Li, L. Zhang, Characterizing the extremal graphs with respect to the eccentricity spectral radius, and beyond, Discrete Math. 345 (2022) 112686].
Citation: Jianping Li, Leshi Qiu, Jianbin Zhang. Proof of a conjecture on the $ \epsilon $-spectral radius of trees[J]. AIMS Mathematics, 2023, 8(2): 4363-4371. doi: 10.3934/math.2023217
The $ \epsilon $-spectral radius of a connected graph is the largest eigenvalue of its eccentricity matrix. In this paper, we identify the unique $ n $-vertex tree with diameter $ 4 $ and matching number $ 5 $ that minimizes the $ \epsilon $-spectral radius, and thus resolve a conjecture proposed in [W. Wei, S. Li, L. Zhang, Characterizing the extremal graphs with respect to the eccentricity spectral radius, and beyond, Discrete Math. 345 (2022) 112686].
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