The 4th Dimension
(Published on 28. April 2025, 19:01 by Fenners)
You've heard of the 3 dimensions of Sudoku: rows, columns and 3x3 boxes. Now we enter the 4th Dimension, and you must construct it! Good luck. P.S, Set at 2 stars but may be closer to 2.5. Thanks to CtC Community for testing :)
Puzzle: The 4th Dimension
Rules:
Normal 9x9 Sudoku rules apply.
Extra Region Construction: There are nine, 9-cell orthogonally connected extra regions in the grid you must construct, where each digit from 1-9 must appear in each extra region.
Arrows: The digits on a tail of an arrow must sum to the digit in the bulb. The tail of an arrow is in the same extra region across it's length but in a different extra region to it's bulb. The digit in the bulb indicates how many cells of it's extra region are in it's 3x3 box.
Solution code: Column 5, top to bottom, 9 digits no spaces:
Comments
on 9. May 2025, 11:22 by botteur
Really nice flow. Loved it
on 8. May 2025, 20:21 by Snookerfan
Brilliant puzzle! Thank you
on 6. May 2025, 22:36 by AngusWBA
Gorgeous puzzle! Thank you.
on 6. May 2025, 21:51 by AngusWBA
Gorgeous puzzle! Thank you.
on 3. May 2025, 17:34 by miss66
very interesting !
on 3. May 2025, 12:42 by Florian Wortmann
Lovely :-)
on 3. May 2025, 00:04 by juddimal
Very nice. Loved the ruleset.
on 1. May 2025, 21:14 by Christounet
Very good execution of the ruleset. Simple and elegant! Thanks :)
on 30. April 2025, 20:36 by koba1917
wow! That was super fun.
on 29. April 2025, 23:43 by Myxo
Brilliant puzzle!
----
Thanks Myxo! :) -- Fenners
on 29. April 2025, 23:17 by polcat
Incredible puzzle! I really loved this. I found it harder than some of the commenters below - about 3.5*
----
Thanks polcat. Setting a difficulty rating had me stumped to be honest, with many conflicting opinions. It has now settled at 3* which I think is reasonable -- Fenners
on 29. April 2025, 12:38 by Franjo
As this ruleset contains a new constraint (though similar to CC) I gave 3*. After I got my brain around the walk on the solving path was a great pleasure! Thank you very much for creating and sharing this lovely puzzle.
——
Happy to hear you enjoyed this, thank you for solving! I was hesitant with the difficulty and originally put is as 3* then lowered it to 2* but with a note it’s more like 2.5 — Fenners
on 29. April 2025, 08:35 by Fenners
Thank you for all your comments! Glad you enjoyed the puzzle :)
on 29. April 2025, 01:40 by mathpesto
Very fun ruleset!
on 28. April 2025, 22:35 by AshBrown
Very nice thanks
on 28. April 2025, 21:50 by mihel111
Easy, but nice and fresh. Not too long for a construction. A pearl of 2*.
on 28. April 2025, 21:20 by welgen
Very nice, approachable region construction sudoku. Thanks for setting!
