Question 83
Find all pairs of positive integers $(m, n)$, $m \le n$, such that there exists an $m \times n$ table of zeros and ones which satisfy the following condition:
If there is a zero (resp. one) in a cell, then the number of the zeros (resp. ones) in the row of that cell is equal to the number of the zeros (resp. ones) in the column of the cell.
If there is a zero (resp. one) in a cell, then the number of the zeros (resp. ones) in the row of that cell is equal to the number of the zeros (resp. ones) in the column of the cell.