Improved Upper Bounds on the Number of Vertices of Weight ≤ k in Particular Arrangements of Pseudocircles
نویسنده
چکیده
In arrangements of pseudocircles (Jordan curves) the weight of a vertex (intersection point) is the number of pseudocircles that contain the vertex in its interior. We give improved upper bounds on the number of vertices of weight ≤ k in certain arrangements of pseudocircles in the plane.
منابع مشابه
UPPER BOUNDS ON THE NUMBER OF VERTICES OF WEIGHT ≤ k IN PARTICULAR ARRANGEMENTS OF PSEUDOCIRCLES
In arrangements of pseudocircles (Jordan curves) the weight of a vertex (intersection point) is the number of pseudocircles that contain the vertex in its interior. We give improved upper bounds on the number of vertices of weight ≤ k in certain arrangements of pseudocircles in the plane. In particular, forbidding certain subarrangements we improve the known bound of 6n − 12 (cf. [2]) for verti...
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تاریخ انتشار 2008