Copyright © University of Cambridge. All rights reserved.
In the grid below, N is a 6 digit number with a very special property: if you double the number and write it in the second row, treble the number and write it in the third row, and so on, you end up with a Latin Square.
A Latin Square is an arrangement of numbers in a square in which each number appears exactly once in each row and column. So, for example, the number represented by ? can't be the same as B or *, and * can't be the same as D, ? or @.