MathDB

We colour all the sides and diagonals of a regular polygon

P

with

43

vertices either red or blue in such a way that every vertex is an endpoint of

20

red segments and

22

blue segments. A triangle formed by vertices of

P

is called monochromatic if all of its sides have the same colour. Suppose that there are

2022

blue monochromatic triangles. How many red monochromatic triangles are there?

Problem Statement