Penpalindromes
(Published on 23. October 2025, 02:04 by cygne)
Penpalindromes by Cygne
Rules
- Normal Sudoku rules apply.
- Digits along gray palindrome lines read the same forward and backward.
- Digits separated by a white Kropki dot are consecutive.
- Digits separated by a black Kropki dot are in a 2:1 ratio.
Play in SudokuPad
After my extremely long modular line puzzle, Modulo Oblongata, I wanted to try to make an extremely long palindrome line. Hope you enjoy!
Solution code: Column 9, top to bottom
Comments
on 9. January 2026, 07:36 by samsamsam1000
new to non-normal sudoku, fun and way easier on my brain that there are no anti-knight shenanigans. Colored everything and needed a friend to help get the first number
on 23. October 2025, 23:17 by Fra314
Letters, then colours, then candidates, then constraints :D
Super fun!
on 23. October 2025, 23:02 by greemi01
that was fun. i prefer letters when so much coloring is needed
on 23. October 2025, 20:23 by dzamie
Very easy if you know how to handle "long palindrome" puzzles. I use colors because filling the box is easier to read than staring at little letters.
on 23. October 2025, 20:03 by damo_89
Team ABC here! No to colours!
on 23. October 2025, 19:21 by UndeadDodo
Going from no digits placed to finished in 30 seconds was very satisfying. Ty for the puzzle. :D
on 23. October 2025, 17:45 by rmulinix
Solved via letters.. nice puzzle.
on 23. October 2025, 16:16 by War
I just read in the comments that someone uses letters instead of coloring for candidate marking. My mind is blown, letters are for disambiguating colors or for candidates in chaos construction when you need colors for regions. This is the only way
on 23. October 2025, 15:20 by Franjo
Funny „Madam, I’m Adam“-construction. Thank you very much for creating and sharing.
on 23. October 2025, 09:36 by BorisTheSnake
Beautiful coloring exercise!
on 23. October 2025, 03:57 by sfield
That was a fun puzzle. I like puzzles that I can solve completely with letters before I even begin to fill in the numbers.
