Mathrax Sudoku
Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.Some intersections of the grid lines are marked by a number and an operator (+, -, x, /) in a circle. The number is the result of the operation, applied to both pairs of diagonally opposite cells. An E in the circle indicates that all four adjacent digits are even, while an O indicates that all four adjacent digits are odd.
Sudokus that no one can solve
Sudokus that no one can solve, not only including Sodukus which is very difficult but also that no one trying to solve it.