Repeated Angles in Three and Four Dimensions

نویسندگان

  • Roel Apfelbaum
  • Micha Sharir
چکیده

We show that the maximum number of occurrences of a given angle in a set of n points in R3 is O(n7/3), and that a right angle can actually occur Ω(n7/3) times. We then show that the maximum number of occurrences of any angle different from π/2 in a set of n points in R4 is O(n5/2β(n)), where β(n) = 2O(α(n) 2) and α(n) is the inverse Ackermann function.

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عنوان ژورنال:
  • SIAM J. Discrete Math.

دوره 19  شماره 

صفحات  -

تاریخ انتشار 2005