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On large distances in planar sets

✍ Scribed by Katalin Vesztergombi


Publisher
Elsevier Science
Year
1987
Tongue
English
Weight
383 KB
Volume
67
Category
Article
ISSN
0012-365X

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✦ Synopsis


Let n k denote the number of times the kth largest distance occurs among a set S of n points in the Euclidean plane. We prove that n2 ~< 2~n for arbitrary set S. This upper bound is sharp.

We consider the set S of n arbitrary points in R 2. We denote the largest distance between two points in S by dl, the second largest by d2. Let us denote by nl resp. n2 the number of distances equal to dl resp. d2. It was proven by Hopf and Pannwitz [1] and Sutherland [2]: Definition. We call a configuration of Fig. 1 a forbidden N.


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