The Two-Coloring Number and Degenerate Colorings of Planar Graphs
نویسندگان
چکیده
The two-coloring number of graphs, which was originally introduced in the study of the game chromatic number, also gives an upper bound on the degenerate chromatic number as introduced by Borodin. It is proved that the two-coloring number of any planar graph is at most nine. As a consequence, the degenerate list chromatic number of any planar graph is at most nine. It is also shown that the degenerate diagonal chromatic number is at most eleven and the degenerate diagonal list chromatic number is at most tweleve for all planar graphs.
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عنوان ژورنال:
- SIAM J. Discrete Math.
دوره 23 شماره
صفحات -
تاریخ انتشار 2009