MathDB
JBMO TST Moldova Problem 3

Source: JBMO TST Moldova Problem 3

October 13, 2020
combinatoricsregular polygon

Problem Statement

Let there be a regular polygon of nn sides with center OO. Determine the highest possible number of vertices kk (k3)(k \geq 3), which can be coloured in green, such that OO is strictly outside of any triangle with 33 vertices coloured green. Determine this kk for a)n=2019a) n=2019 ; b)n=2020b) n=2020.