Zipper Galaxies
(Published on 4. February 2024, 18:44 by gdc)
This is a trimmed down version of Galaxy Count: Green and Lavender. It still uses spiral galaxies with galaxy types but no fog and no counting circles. Hope you enjoy!
- Normal Sudoku rules apply.
- Each diamond marks the center of a galaxy. Galaxies are orthogonally connected groups of 1 or more cells that are rotationally symmetric around their centers. Each cell is part of a galaxy and all galaxy centers are given. Digits may not repeat in a galaxy.
- Galaxies with lavender diamonds are zipper galaxies. A digit in a zipper galaxy and its rotational counterpart sum to the same number. If the galaxy contains an odd number of cells, that total is equal to the central cell.
- Galaxies with pink diamonds are renban galaxies. Digits in a renban galaxy are contiguous.
Examples
Here are examples for the galaxy types. The first image shows an odd zipper galaxy. The central digit is an 8 so all rotational pairs (17, 26, 35) sum to 8. The second image show an even zipper galaxy where the rotational pairs (15, 24) all sum to 6. The third image shows a renban galaxy. The digits in that galaxy form a contiguous run (45678) without skipping digits when sorted.
Hint
Which galaxy center belongs to R6C5?
Solution code: column 1
Comments
on 27. September 2024, 10:54 by QuiltyAsCharged
Terrific puzzle. For me the hardest part was not actually the galaxy construction, it was determining the center digits of the zipper galaxies and a few other initial digits.
on 14. June 2024, 13:43 by Geb
It is so easy to make false steps during the early galaxy drawing phase! I had to backtrack a few times after running into contradictions. Once you get into actually placing digits it's a lot smoother. Incredibly clever puzzle.
on 12. February 2024, 20:14 by samuel1997
This is brilliant!
on 8. February 2024, 10:50 by LehanLehan
A really beautiful puzzle, the solve path is solid and fair;hard,rewarding and very interesting journey. Thank you very much, gdc.
on 7. February 2024, 16:55 by madhupt
This is an absolutely fantastic puzzle! I did not assume that the zipper or renban galaxies cannot be one cell long, still was able to solve it. Required quite a bit of staring a the puzzle and trying to find the cells which could belong to only one galaxy but each deduction brought forth the next one a really delicious manner. Really, really enjoyable. Thanks a lot for sharing!
on 6. February 2024, 12:41 by Nurator
Really beautiful construction! Both the galaxy building and the actual Sudoku had really clever deductions.
on 5. February 2024, 11:23 by echidna
Incredible puzzle, with some absolutely beautiful deductions! Probably the best galaxy puzzle I’ve ever solved.
on 4. February 2024, 23:43 by Flinty
Excellent puzzle. Thank you for setting.
on 4. February 2024, 23:16 by gdc
add hint
