Sub-exponentially many 3-colorings of triangle-free planar graphs
نویسندگان
چکیده
Thomassen conjectured that every triangle-free planar graph on n vertices has exponentially many 3-colorings, and proved that it has at least 2 1/12/20000 distinct 3-colorings. We show that it has at least 2 √ n/362 distinct 3-colorings. April 2010, revised 8 July 2010. An extended abstract of this paper appeared in [1]. Partially supported by an NSF Graduate Research Fellowship. Partially supported by NSF under Grant No. DMS-0701077.
منابع مشابه
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ورودعنوان ژورنال:
- Electronic Notes in Discrete Mathematics
دوره 34 شماره
صفحات -
تاریخ انتشار 2009