MathDB
a convex n gon

Source: Bulgaria TST 2003 P3

September 8, 2012
inductioncombinatorial geometrycombinatorics proposedcombinatorics

Problem Statement

Some of the vertices of a convex nn-gon are connected by segments, such that any two of them have no common interior point. Prove that, for any nn points in general position, there exists a one-to-one correspondence between the points and the vertices of the nn gon, such that any two segments between the points, corresponding to the respective segments from the nn gon, have no common interior point.