Can you fill a 4x4 square so each row and each column forms a prime number? And a 5x5 square?
Note: in both cases, there should be no duplicate rows or duplicate columns. Also, numbers cannot start with a 0. Finally, all digits from 0 to 9 should be used at least once.
(In reply to Part One -- a solution at random
Done similarly to part 1, so probably a lot more exist:
Posted by Charlie
on 2005-07-19 16:06:30