2016 IMO Problems/Problem 2
Find all integers for which each cell of table can be filled with one of the letters and in such a way that:
Note. The rows and columns of an table are each labelled to in a natural order. Thus each cell corresponds to a pair of positive integer with . For , the table has diagonals of two types. A diagonal of first type consists all cells for which is a constant, and the diagonal of this second type consists all cells for which is constant.