EMPTY CONVEX 5-GONS IN PLANAR POINT SETS

• Ann, Seong-Yoon (Department of Mathematics, Graduate School of Education, Chosun University) ;
• Kang, En-Sil (Department of mathematics, College of Natural Sciences, Chosun University)
• Accepted : 2009.08.05
• Published : 2009.09.25
• 62 3

Abstract

Erd$\"{o}$s posed the problem of determining the minimum number g(n) such that any set of g(n) points in general position in the plane contains an empty convex n-gon. In 1978, Harborth proved that g(5) = 10. We reprove the result in a geometric approach.

Keywords

Combinatorial geometry;convex polygon

References

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