Cut off the 4 corner squares of the 3x4 rectangular grid.
Now place the digits 1 to 8 in the remaining 8 squares in a way.
such that no adjacent numbers are in adjacent squares (horizontally, vertically, or diagonally).
How many different solutions exist?

There is essentially one solution:

 35
7182
 46

Counting reflections and rotations there are 4 solutions.

Posted by Jer on 2013-01-31 16:45:38