The 4-Colour Theorem
(Published on 5. February 2023, 10:00 by starwarigami)
- Digits may not repeat in a cage.
- Digits in a cage sum to one of 4 distinct totals.
- No two touching cages may sum to the same total.
Walkthrough
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Solution code: Column 1, Column 2 - 18 digits, no spaces
Comments
on 30. June 2023, 09:46 by zhall12570
Although it's rated harder, I found this one smoother than the 3-color theorem puzzle. Both are fantastic!
on 25. April 2023, 17:12 by Bankey
Boy, that was a tough one! But very enjoyable. Thanks for setting, @ starwarigami :)
on 20. April 2023, 08:05 by dennischen
Real colourful fun! No individual step was super hard, but considering everything in its totality and then breaking it down was a lot of fun :)
(I *did* have to open up Vim to take some notes, so it is still 5*.)
on 19. February 2023, 15:12 by Hydalin
This was one of the hardest, most challenging sudokus ever. Took me several evenings, three tries and a total of 8-10 hours. Really interesting setting and brilliant interactions of all the constraints. Thanks a lot for that jewel!
@Hydalin: I'm flattered that you deemed the puzzle worthy of so much of your time! Thanks so much for sticking with it
on 8. February 2023, 18:57 by SudokuExplorer
Excellent puzzle with a cool concept and interesting logic! :-)
on 8. February 2023, 09:10 by ddx2407
What an amazing puzzle. Not brutally hard, to my opinion, but super interesting, and some neat deductions. Very well done. Thank you, @starwarigami!
on 6. February 2023, 20:38 by Yawnus
This ruleset is quite fascinating. Other puzzles using the same rules are 0005V3, 0008WS and 000A3I, if anyone is interested to try.
@Yawnus: thanks for the heads up re. the similar puzzles - I'll be sure to take a look!
on 6. February 2023, 20:35 by KNT
What a battle! Thank you for this challenging killer.
on 6. February 2023, 11:45 by DVFrank
What a brilliant construction! :^)
on 5. February 2023, 18:04 by giladooshlon
I just love puzzles like this
on 5. February 2023, 12:42 by Myxo
Very nice!
