Normal Sudoku rules apply.
Zipper Lines : On purple zipper lines, digits that are at an equal distance away from the center must have the same sum. If the line is of odd length, the sum is the digit on the center.
Anti-Quads : Digits in a white circle must NOT appear in the four cells touching that circle.
Solution code: Row 2
today, 07:08 by rameshsrivats
Fachinating interplay of modular and entropic sets