X-Fold Antisymmetry
(Published on 15. January 2025, 20:04 by juggler)
In each grid, normal 4x4 Sudoku rules apply.
X-SUMS - On each grey tab, write some number that acts as an "x-sums" clue in both directions, i.e. moving into a grid from the tab, the first N cells sum to its number, where N is the first digit seen. (Different tabs may have different X-sums.)
FOLDED ANTISYMMETRY - If the puzzle were folded along one dashed line, and then along the other, no digit would overlap another identical digit.
Solution code: Bottom row (9 digits)
Comments
on 8. January 2026, 23:41 by dzamie
Pretty mind-bending at first! Got much easier once I figured out how to keep track of which cells would fold onto each other (there's 16 cells in the folded grid, so I had to use pairs of colors instead of individual colors)
on 23. October 2025, 17:14 by Voidslime
What a cool take on disjoint! Thanks for linking this in next to X! After a certain point i was completing the boxes on the symmetry rule so much i forgot about basic rows and columns. It made me realize that a disjoint set is mathematically equivalent to row or column and now my mind is full of 3d cubes
on 4. April 2025, 00:18 by The Book Wyrm
Fun and clean solve, very impressive for only 3 clues. Cool puzzle, thanks.
on 15. January 2025, 22:39 by Puzzle Weasel
So very neat, thank you.
on 15. January 2025, 21:08 by DubiousMobius
I really enjoyed this take on disjoint grids. Lovely when a puzzle encourages you to imagine crumpling it up a little before you even begin!
