MathDB
polyline which edges connect the midpoints of two adjacent edges of the previous

Source: 239 2015 J7

May 17, 2020
combinatorics

Problem Statement

There is a closed polyline with nn edges on the plane. We build a new polyline which edges connect the midpoints of two adjacent edges of the previous polyline. Then we erase previous polyline and start over and over. Also we know that each polyline satisfy that all vertices are different and not all of them are collinear. For which nn we can get a polyline that is a сonvex polygon?