Logic Masters Deutschland e.V.

Rules
Place the digits 1 to 9 once each into each box. Digits may not repeat in the same row, column, or box of the grid.
Cells separated by a knight's move cannot contain the same digit.
The sum of the digits along an orange "double arrow" line is equal to the sum of the digits in the circles at each end of the line.
The digits along the blue "single arrow" must sum to the digit in the circled cell.
Black dots join cells with a 1:2 ratio. Not all dots are given.

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