Planar Graphs Have Exponentially Many 3-Arboricities
نویسندگان
چکیده
It is well-known that every planar or projective planar graph can be 3-colored so that each color class induces a forest. This bound is sharp. In this paper, we show that there are in fact exponentially many 3-colorings of this kind for any (projective) planar graph. The same result holds in the setting of 3-list-colorings.
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عنوان ژورنال:
- SIAM J. Discrete Math.
دوره 26 شماره
صفحات -
تاریخ انتشار 2012