Logic Masters Deutschland e.V.

If you are interested in the Dutch Flat Mates series created by Flinty, you can find the others here.

Normal sudoku rules apply.

• Dutch Flats : Every 5 in the grid must have a '1' directly above it or a '9' directly below it. It may have both, but it doesn't need both.


• Mathrax : 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; an "O" indicates that all four adjacent digits are odd.

The puzzle is available online via CTC-App