Vertex coloring the square of outerplanar graphs of low degree
نویسندگان
چکیده
Vertex colorings of the square of an outerplanar graph have received a lot of attention recently. In this article we prove that the chromatic number of the square of an outerplanar graph of maximum degree ∆ = 6 is 7. The optimal upper bound for the chromatic number of the square of an outerplanar graph of maximum degree ∆ 6= 6 is known. Hence, this mentioned chromatic number of 7 is the last and only unknown upper bound of the chromatic number in terms of ∆.
منابع مشابه
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عنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 30 شماره
صفحات -
تاریخ انتشار 2010