Local chromatic number and topological properties of graphs
نویسندگان
چکیده
The local chromatic number of a graph, introduced by Erdős et al. in [3], is the minimum number of colors that must appear in the closed neighborhood of some vertex in any proper coloring of the graph. This talk, based on the papers [13, 14, 15], would like to survey some of our recent results on this parameter. We give a lower bound for the local chromatic number in terms of the lower bound of the chromatic number provided by the topological method introduced by Lovász. We show that this bound is tight in many cases. In particular, we determine the local chromatic number of certain odd chromatic Schrijver graphs and generalized Mycielski graphs. We further elaborate on the case of 4-chromatic graphs and, in particular, on surface quadrangulations.
منابع مشابه
Local chromatic number and topological properties of graphs ( Extended abstract )
The local chromatic number of a graph, introduced by Erdős et al. in (4), is the minimum number of colors that must appear in the closed neighborhood of some vertex in any proper coloring of the graph. This talk, based on the papers (14; 15; 16), would like to survey some of our recent results on this parameter. We give a lower bound for the local chromatic number in terms of the lower bound of...
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