EMPTY CONVEX 5-GONS IN PLANAR POINT SETS
EMPTY CONVEX 5-GONS IN PLANAR POINT SETS
Erd<TEX>$\"{o}$</TEX>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.