The absolute values are just 1, 2, 3, 4, 5, 6, 7, 8, 9, so their sum is 45, that is, the sum of the absolute values of three numbers in each row, column and diagonal is 45÷3= 15, and the number of nine square centers is in this row and column *.

1+2+3+4+5+6+7+8+9+(4-1) x =15× 4, and the solution is x=5, then the number of centers can be determined as -5.