Problems and Results around the Erdös-Szekeres Convex Polygon Theorem
نویسندگان
چکیده
Eszter Klein’s theorem claims that among any 5 points in the plane, no three collinear, there is the vertex set of a convex quadrilateral. An application of Ramsey’s theorem then yields the classical Erdős–Szekeres theorem [19]: For every integer n ≥ 3 there is an N0 such that, among any set of N ≥ N0 points in general position in the plane, there is the vertex set of a convex n-gon. Let f(n) denote the smallest such number.
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