NOTE:
CALCUDOKU FROM ZERO 7x7 is a logical-mathematical game in which you have to fill a 7x7 square with the digits 0, 1, 2, 3, 4, 5, 6. You can't have the same digit in the same row or column.
For each region a number and a mathematical operation indicate that, applying that operation to all the digits in the region (note that the order doesn't matter), you must obtain that result.