Sophie colors every triangle side in red, green or blue in 12 triangles fig.
Source: 2021 Francophone MO Juniors p2
April 3, 2021
Coloringcombinatoricsgraph theorycountingFrancophone
Problem Statement
Evariste has drawn twelve triangles as follows, so that two consecutive triangles share exactly one edge.
https://cdn.artofproblemsolving.com/attachments/6/2/50377e7ad5fb1c40e36725e43c7eeb1e3c2849.png
Sophie colors every triangle side in red, green or blue. Among the possible colorings, how many have the property that every triangle has one edge of each color?