Coloring the cliques of line graphs
نویسندگان
چکیده
The weak chromatic number , or clique chromatic number (CCHN) of a graph is the minimum number of colors in a vertex coloring, such that every maximal clique gets at least two colors. The weak chromatic index , or clique chromatic index (CCHI) of a graph is the CCHN of its line graph. Most of the results here are upper bounds for the CCHI, as functions of some other graph parameters, and contrasting with lower bounds in some cases. Algorithmic aspects are also discussed; the main result within this scope (and in the paper) shows that testing whether the CCHI of a graph equals 2 is NP-complete. We deal with the CCHN of the graph itself as well.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 340 شماره
صفحات -
تاریخ انتشار 2017