On the Chromatic Number of Simple Triangle-Free Triple Systems
نویسندگان
چکیده
A hypergraph is simple if every two edges share at most one vertex. It is trianglefree if in addition every three pairwise intersecting edges have a vertex in common. We prove that there is an absolute constant c such that the chromatic number of a simple triangle-free triple system with maximum degree ∆ is at most c √ ∆/ log ∆. This extends a result of Johansson about graphs, and is sharp apart from the constant c.
منابع مشابه
The triangle chromatic index of Steiner triple systems
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متن کاملComment on “ On the chromatic number of simple triangle - free triple systems ”
We have found several errors in the paper [1] and the goal here is to present corrections to all of them. Equational references with square brackets [..] are with respect to the published version. Those with round brackets (..) are with respect to this comment. The notation is from [1]. There was a substantial error in the proof of [15] (in Section 11.4.1 of [1]) and a trivial error in the calc...
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عنوان ژورنال:
- Electr. J. Comb.
دوره 15 شماره
صفحات -
تاریخ انتشار 2008