ell, all possible entries that will not contradict the One Rule with respect to the
n cells. If a celle ends ♣ up having only one possibles entry, it is a "forced" entre
you should fill in. The Math Behind S
the fact ♣ that every row, column and block must
ntain each of the numbers 1 to 9 once. Therefore, the total of all ♣ num bers in one roW,
