**Problem of the Week-2: Double-Diagonal Latin Square **

A Latin square of order n is an n by n array filled with n different symbols such that each symbol occurs exactly once in each row and exactly once in each column. A double-diagonal Latin square has the additional requirement that each symbol occurs exactly once in each diagonal. Complete the blank cells in the table below (with numbers 1,2,3,4) so that it is a double diagonal Latin square of order 4. Is there a unique solution or do there exist more than one solutions?

1 | 2 | 3 | 4 |

Posted: 9-10-07

Submit your answers (by e-mail or hard copy) before 4 pm on 9-21-07 to Noah Aydin.

Mathematics Dept.