Tightness problems in the plane
نویسندگان
چکیده
A 3-uniform hypergraph is called tight if for any 3-coloring of its vertex set a heterochromatic edge can be found. In this paper we study tightness of 3-graphs with vertex set IR and edge sets arising from simple geometrical considerations. Basically we show that sets of triangles with \fat shadows" are tight and also that some interesting sets of triangles with \thin shadows" are tight.
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عنوان ژورنال:
- Discrete Mathematics
دوره 194 شماره
صفحات -
تاریخ انتشار 1999