MathDB
MMO 358 Moscow MO 1957 closed broken line in space, no of segments div. by 6

Source:

August 20, 2019
combinatorial geometrybroken line3D geometrygeometryperpendicular

Problem Statement

The segments of a closed broken line in space are of equal length, and each three consecutive segments are mutually perpendicular. Prove that the number of segments is divisible by 66.