In Newtown Middle School, there was a school boy named Chris who was an absolute troublemaker. One of his many schemes against the school was drawing squares in permanent marker on all the walls in the school. Thus, when the school decided to make a punishment for Chris, they decided to do something involving squares.

The school made Chris create all possible unique Greco-Latin squares using A-D and 1-4. (A 4x4 Greco-Latin square using A-D and 1-4 is a special 4x4 square. Each cell of the square has exactly one letter of the four and one number of the four within it. The end result will have every letter and every number used once in each row, column, and main diagonal of the square.)

Chris is a very slow boy, and after several hours, he figured out all the possible Greco-Latin squares. How many squares did he find?

(In reply to re: Solution by Tristan)

Tristan wrote:

"Among the combinations you include, this would be one:

A1 B2 C3 D4
C3 D4 A1 B2
D4 C3 B2 A1
B2 A1 D4 C3

A brief look at this shows that it does not count. "

This is one of the reasons I flunked out of Newtown Middle School. I am slower than Chris. The example you cite as invalid, has "every letter and every number used once in each row, column, and main diagonal of the square". That is the specification of the puzzle. I cannot read Victor Zapana's mind. I can only go by what the puzzle says. Why doesn't it count ? Are we supposed to solve these puzzles, based on their wording "before they were edited in the queue", when that is not even visible to us ? 

 

 

 

Edited on May 3, 2004, 2:08 am

Posted by Penny on 2004-05-03 01:53:00