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?
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