How to play ?

Fill in the board with all the counters so that each color and figure on the counter appears exactly once in each row and in each column, ie, that there is no row or column where the color or the figure on the counter is repeated.

Different modes:

3×3 board, easy mode: this option is the easiest, and it is also aimed at children as graphic counters can be selected. This mode is the easiest to learn how to play the game.

4×4 board, intermediate mode: this mode offers the option of saving games. We can always keep on playing the latest game that we have saved.

5×5, advanced mode: this is the hardest mode. In this mode you can also save the game, as in the previous option.

Leaderboard:

In the 4×5 and 5×5 modes we can see the best players’ ranking sorted by number of movements and mistakes made.

A little history. What is a Graeco-Latin square?

In mathematics, a Graeco-Latin square or Euler square or orthogonal Latin squares of order n over two sets S and T, each consisting of n symbols, is an n×n arrangement of cells, each cell containing an ordered pair (s,t), where s is an element of S and t is an element of T, so that every row and column contains each element of S and each element of T exactly once, and that there are not two cells containing the same ordered pair.(Wiki)

Graeco-Latin squares are highly recommended as a mental exercise, and solving them may help slow down the progression of diseases such as Alzheimer.

The Sudoku puzzles are actually a special instance of Latin squares, a variant of Graeco-Latin squares.