Logic Masters Deutschland e.V.

Zipper Lines: Pairs of digits an equal distance from the center of a line have the same sum. If the center of the line coincides with a digit, that digit must be the line's common sum.

Each line must also obey one of the following:

Entropic Lines: Along an entropic line, any group of three consecutive cells must contain on low {1,2,3}, one medium {4,5,6}, and one high {7,8,9} digit.

German Whispers: Along a whisper line, adjacent digits must differ by at least 5.

Modular Lines: Along a modular line any three adjacent digits must all have different remainders when divided by 3.

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