Evariste has drawn twelve triangles as follows, so that two consecutive triangles share exactly one edge. Sophie colors every triangle side in red, green or blue. Among the $3^{24}$ possible colorings, how many have the property that every triangle has one edge of each color?
Problem
Source: 2021 Francophone MO Juniors p2
Tags: Coloring, combinatorics, graph theory, counting, Francophone
