Signless Laplacian spectral radii of graphs with given chromatic number
نویسندگان
چکیده
منابع مشابه
Spectral radii of graphs with given chromatic number
We consider the set Gn,k of graphs of order n with the chromatic number k ≥ 2. In this note, we prove that in Gn,k the Turán graph Tn,k has the maximal spectral radius; and Pn if k = 2, Cn if k = 3 and n is odd, C1 n−1 if k = 3 and n is even, K (l) k if k ≥ 4 has the minimal spectral radius. Thus we answer a problem raised by Cao [D.S. Cao, Index function of graphs, J. East China Norm. Univ. Sc...
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ژورنال
عنوان ژورنال: Linear Algebra and its Applications
سال: 2011
ISSN: 0024-3795
DOI: 10.1016/j.laa.2011.03.018