Question 9
Each $1\times1$ tile has a red side opposite a yellow side, and a blue side opposite a green side. An $8\times8$ chessboard is formed from $64$ of these tiles, which may be turned around or turned over. When two tiles meet, the edges that come together must be of the same colour. How many different chessboards can be formed? Turning the chessboard around or turning the chessboard over is not allowed.