Logic Masters Deutschland e.V.

The central box and the whole grid are magic squares (all three/nine cell long diagonal, horizontal and vertical lines sum to the same number and cannot repeat digits).

The tartan line surrounding the central box is a Scottish Sum Line (going in one direction only) where each digit is the sum of the two preceding cells (if the digits sum to more than ten then only the unit digit is used).

Purple lines are consecutive digits in any order.

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