Complete solution to a conjecture on the Randić index of triangle-free graphs
نویسندگان
چکیده
منابع مشابه
On Reed's Conjecture in Triangle-Free Graphs
The problem of finding the chromatic number of a graph G, i.e. the minimum number of colors needed to assign distinct colors to adjacent nodes of G, is NP-complete. However, there are some known bounds including the trivial lower bound χ(G) ≥ ω(G) and the upper bound provided by Brooks [2] χ(G) ≤ ∆(G) + 1, where χ(G) denotes the chromatic number, ∆(G) the maximum degree and ω(G) the number of n...
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Xueliang Li a, Haixing Zhao b and Lusheng Wang c a Center for Combinatorics, Nankai University, Tianjin 300071, P.R. China E-mail: [email protected] b Department of Computer Science and Engineering, Northwestern Polytechnical University, Xi’an, Shaanxi 710072, P.R. China E-mail: [email protected] c Department of Computer Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, P....
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2009
ISSN: 0012-365X
DOI: 10.1016/j.disc.2009.06.003