Palindromic Little Killer X Sudoku
(Published on 23. February 2021, 01:00 by SudokuExplorer)
Each row, column, box and marked diagonals contain the digits 1 to 9.
Standard little killer rules apply.
A number outside the grid is the sum of all digits (not necessarily distinct) on the diagonal in the direction of the little arrow.
Standard palindrome line rules apply.
Each grey line reads the same from either end (eg 1551 or 7227).
You can attempt this on Penpa+ or F-Puzzles. Enjoy!
Solution code: Enter the 2nd row and 2nd column
Comments
on 17. January 2023, 04:23 by pg805
Found this puzzle about a year ago, spent 10 hours on it, forgot about it, came back to it, spent another 20 hours on it and finally made some progress. Fantastic and Beautiful puzzle.
on 2. August 2021, 02:53 by SudokuExplorer
Fixed tags/labels
on 6. June 2021, 23:20 by SudokuExplorer
@Goofy: Very well done in getting through this toughie! The break-in is challenging if one hasn't seen a similar idea before and still remains challenging after, so thanks for persevering to find the logic :-)
on 4. June 2021, 15:47 by Goofy
After 2 months I placed the first digit. An hour later the puzzle was done.
Holy geebes
on 27. February 2021, 17:44 by henrypijames
I'm amazed such a difficult puzzle has been solved by so many people in just a few days.
on 25. February 2021, 02:18 by SudokuExplorer
@Franjo:
I'm pleased you had fun colouring the grid. Thanks for giving it a go and for your kind feedback. :-)
on 25. February 2021, 02:16 by SudokuExplorer
@Bobby: Thanks for the lovely feedback! I'm glad you enjoyed the opening logic, and well-done in getting through it. :-)
on 25. February 2021, 02:13 by SudokuExplorer
@Dina + @Swood:
I'm glad you both enjoyed the geometric interaction of the constraints. Thanks :-)
on 24. February 2021, 20:25 by Franjo
What a colorful Piece of Sudoku Art!
Love it.
on 24. February 2021, 17:50 by Swood
Thanks for the geometry lesson!
on 24. February 2021, 06:30 by Bobby
Beautiful break-in!!!
It still remained tricky afterwards too. Thanks!
on 23. February 2021, 17:03 by Dina
Another masterpiece! The geometry was stunning as usual.
on 23. February 2021, 14:07 by SudokuExplorer
@Storm + @TotallyNormalCat:
Firstly thanks for giving it a go!
This is probably the most challenging puzzle I've created, so congrats for solving it! :-)
I will likely describe my thinking process in a hidden comment later on.
on 23. February 2021, 03:39 by Storm
This is a party for any geometer!
One of the hardest and coolest puzzles I've ever solved.
on 23. February 2021, 02:48 by TotallyNormalCat
This is one of the best puzzles I've seen, how is it possible for 1 person to be this good at setting???
