A Latin square is an n x n squared table filled with different symbols in such a way that each symbol
occurs exactly once in each row and exactly once in each column.

1

2

2

3

1

2

3

2

3

1

3

1

2

The name Latin square were introduced by Leonhard Euler in 1783.
The numbers of Latin squares of order , 2, ... are 1, 2, 12, 576, 161280, ...