MathDB
2-coloring 2n-gon, sequence of side lengths are equal

Source: VJIMC 2000 1.4

July 27, 2021
geometry

Problem Statement

Let us choose arbitrarily nn vertices of a regular 2n2n-gon and color them red. The remaining vertices are colored blue. We arrange all red-red distances into a non-decreasing sequence and do the same with the blue-blue distances. Prove that the sequences are equal.