I haven't seen this variant before, so I named it Doubles Sudoku. Nice new logic is needed to solve this puzzle, so I hope you'll like it :)
Rules: Place the digits 1-9 exactly once in each 3x3 block.
In row n and column n, digit n must be placed twice. (So, for example, in row 1 the digit 1 must be placed twice and in column 5 the digit 5 twice.) Other digits may not repeat in that row or column.
The puzzle is also available on Penpa. You can use the empty cells at the right and bottom to note which number is absent in that row or column.
Once you've found out the logic of this variant it shouldn't be too hard. If you struggle solving it, find a hint here
.Solution code: Column 5 and column 7.
on 15. March 2024, 12:47 by zrbakhtiar
https://sudokupad.app/rjh12e9m3m
on 9. August 2020, 17:36 by Xavien
Very nice and mind bending, even when you know the strategy
on 7. August 2020, 09:49 by Luigi
Very nice!
on 7. August 2020, 06:24 by Richard
@Statistica: I have good news and bad news for you: The bad news is that this one won't be part of SVS, since the ruleset violates too much with that of a normal sudoku. The good news is that Tom did also submit two puzzles of this type for the website of WCPN. It may take a while (we have a lot of puzzles in stock from Tom) but eventually they will show up there. :-)
on 6. August 2020, 21:00 by SudokuExplorer
Nice concept with interesting logic! Thanks for the fun puzzle :-)
on 6. August 2020, 19:16 by Genomico
Thank you all for the nice comments :)
on 6. August 2020, 12:51 by Statistica
Fantastic. Even it's no Sudoku, as Richard mentioned, I hope we will find it one day in the SVS :-)
on 6. August 2020, 09:06 by Tojvoh
A beautiful Ruleset!
Just fantastic - Thanks for the Puzzle.
on 6. August 2020, 08:44 by Narayana
Perhaps anti-sudoku or double-anti-sudoku or
"CRAS: Column-Row-Anti-Sudoku"
would be a more fitting name?
Reply @Narayana: Nice suggestions :) Or something with Deficit ánd Surplus. Perhaps Double Dutch Deficit and Surplus Sudoku? :D :P
on 6. August 2020, 07:40 by Richard
Looking at the current explorations that are applied by the WPF, concerning 'what is a sudoku' I would say that the constraint of repeating digits makes this explicitly not a sudoku.
For what it's worth. :-)
on 6. August 2020, 06:18 by panthchesh
This is a very fun puzzle!! Thanks for giving a little room outside the grid! It really helped to write the missing number for the row there!
on 6. August 2020, 03:20 by Greg
Nice puzzle. Was convinced it was broken every 5 seconds but bit by bit it all came together.