Unicyclic Graphs of Minimal Spectral Radius

被引：0
作者：
Ling Sheng SHI [1 ]
机构：
[1] Department of Mathematical Sciences,Tsinghua University
来源：
Acta Mathematica Sinica,English Series | 2013年 / 02期
关键词：
Extremal graph; Li–Feng’s conjecture; spectral radius; unicyclic;
D O I：
暂无
中图分类号：
O157.5 [图论];
学科分类号：
070104 ;
摘要：
It was conjectured by Li and Feng in 1979 that the unicyclic graph formed by a cycle of order g linking to an endvertex of a path of length k minimizes the spectral radius of all unicyclic graphs of order g + k and girth g. In 1987, Cao proved that this conjecture is true for k ≥ g(g 2)/8 and false for k = 2 and sufficiently large g. In this note, we show that g > 12 suffices for the counterexample and give more counterexamples with large girth for any integer k > 1.
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页码：281 / 286
页数：6
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