you can divide a square into n dominoes for all n >= 5 , but not for n=3 or 4
Source: Flanders Math Olympiad 2022 p2
December 24, 2022
combinatoricscombinatorial geometrydominoes
Problem Statement
A domino is a rectangle whose length is twice its width.
Any square can be divided into seven dominoes, for example as shown in the figure below.
https://cdn.artofproblemsolving.com/attachments/7/6/c055d8d2f6b7c24d38ded7305446721e193203.png
a) Show that you can divide a square into dominoes for all .
b) Show that you cannot divide a square into three or four dominoes.