摘要
设Gkn(k≥2)为n阶的染色数为k的连通图的集合.本文确定了Gnk中具有极大无符号Laplace谱半径的图,即k =2时为完全二部图,k≥3时为Turán图.本文也讨论了Gnk中的具有极小无符号Laplace谱半径的图,对k≤3的情形给出了此类图的刻画.
Let (k ≥ 2) be the set of all connected graphs of order n with chromatic number k. We determine the graphs with maximal signless Laplacian spectral radius among all graphs in , namely complete bipartite graphs for k = 2 and Turin graph for k ≥ 3. We also consider the graphs with minimal signless Laplacian spectral radius in , and characterized such graphs for k ≤3.
出处
《应用数学》
CSCD
北大核心
2009年第1期161-167,共7页
Mathematica Applicata
基金
Supported by National Natural Science Foundation of China(10601001)
Anhui Provincial Natural Science Foundation(050460102 ,070412065)
NSF of Depart ment of Education of Anhui Province (2005kj005zd)
Foundation of Innovation Teamon Basic Mathematics of Anhui University
Foundation of Talents Group Construction of Anhui University .