Two combinatorial problems in the plane
نویسندگان
چکیده
منابع مشابه
Some Combinatorial Problems in the Plane
1 Let there be given n points in the plane. Denote by t i the number of lines which contain exactly i of the points (2 < i < n). The properties of the set {ti } have been studied a great deal. For example, there is the classical result of Gallai and Sylvester : Assume to = 0 (i .e ., the points are not all on one line) ; then t2 > 0. For the history of this problem see, e.g ., Motzkin [6] and E...
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We study three problems in combinatorial geometry. The problems investigated are con ict-free colorings of point sets in the plane with few colors, polychromatic colorings of the vertices of rectangular partitions in the plane and in higher dimensions and polygonalizations of point sets with few re ex points. These problems are problems of discrete point sets, the proofs are of combinatorial av...
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K. Adaricheva and M. Bolat have recently proved that if $,mathcal U_0$ and $,mathcal U_1$ are circles in a triangle with vertices $A_0,A_1,A_2$, then there exist $jin {0,1,2}$ and $kin{0,1}$ such that $,mathcal U_{1-k}$ is included in the convex hull of $,mathcal U_kcup({A_0,A_1, A_2}setminus{A_j})$. One could say disks instead of circles.Here we prove the existence of such a $j$ and $k$ ...
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ژورنال
عنوان ژورنال: Discrete & Computational Geometry
سال: 1995
ISSN: 0179-5376,1432-0444
DOI: 10.1007/bf02574054