The maximum Laplacian separator of $ k $-cyclic graph
Guidong YU1,2,*(), Zheng RUAN1, Axiu SHU1
1. School of Mathematics and Physics, Anqing Normal University, Anqing 246133, Anhui, China 2. Department of Public Teaching, Hefei Preschool Education College, Hefei 230013, Anhui, China
设$ G $是一个$ n $阶$ k $圈图, $ k $圈图为边数等于顶点数加$ k-1 $的简单连通图。$ \mu_{1}(G) $、$ \mu_{2}(G) $分别记为图$ G $的Laplace矩阵的最大特征值和次大特征值, 图$ G $的Laplace分离度定义为$ S_{L}(G)=\mu_{1}(G)-\mu_{2}(G) $。本文研究了给定阶数的$ k $圈图的最大Laplace分离度, 并刻画了相应的极图, 其结果推广了已有当$ k=1, 2, 3 $时的结论。
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