Logic Masters Deutschland e.V.

Kropki Pairs: Cells separated by a white dot must contain consecutive digits. Cells separated by a black dot must contain digits in a ratio of 1:2. Not all possible dots are necessarily given

159/Indexing: The digit in any cell specifies the column in which its column's number appears in its row. (i.e. if r3c4 contained a 7, r3c7 would need to contain a 4.)

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