Asymptotics of the chromatic number for quasi-line graphs
نویسندگان
چکیده
As proved by Kahn, the chromatic number and fractional chromatic number of a line graph agree asymptotically. That is, for any line graph G we have χ(G) ≤ (1 + o(1))χf (G). We extend this result to quasi-line graphs, an important subclass of claw-free graphs. Furthermore we prove that we can construct a colouring that achieves this bound in polynomial time, giving us an asymptotic approximation algorithm for the chromatic number of quasi-line graphs.
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عنوان ژورنال:
- Electronic Notes in Discrete Mathematics
دوره 29 شماره
صفحات -
تاریخ انتشار 2007