Dutch Flat Mates (Counting Circles)
(Published on 10. April 2024, 11:30 by Flinty)
Normal Sudoku rules apply.
Place the digits 1-9 so that they do not repeat in any row, column, or 3x3 box.
Digits may not repeat along the indicated diagonals.
5's live in Dutch Flats
All 5's in the grid must have a '1' directly above it or a '9' directly below it. It may have both, but it doesn't need both.
Counting Circles
If a digit is in a Circle, exactly that many instances of that digit must appear in Circles.
5s live in Dutch Flats, they don't live in Circles.
To play this puzzle please click here: Play CTC
Previous puzzles in the Dutch Flat Mates series:
- Classic
- Thermometers
- German Whispers
- Region Sum Lines
- Sandwich Sums
- Little Killer
- Kropki
- Zipper Lines
- Renban - By GoodCity
- Nabner - By GoodCity
- Skyscrapers - By GoodCity
- Dutch Whispers
- Killer Cages
- Arrows
- Ten Lines
- 159 and Even - By GoodCity
- Friendly Cells
- Quads
- Silent Killer - By GoodCity
- XV and Equality
- X-Sums
- Numbered Rooms - By GoodCity
- Diagonal X-Sums
- Yin Yang (Neighborhoods) - By Palpot
- Hit Points
Hint 1 - Number of Circles - to save you counting
There are 28 Circles.
Hint 2 - Something to ponderThere are no Circles on either diagonal.
Hint 3 - Where to look firstUsing the rules about 5s not living in Circles, Box 2 having 6 circles, and the empty regions on the diagonals; we can deduce what digits are not in Circles.
Hint 4 - Where to look nextUsing that knowledge, it is actually possible from the start to logically place all 8s (with Counting Circles logic); and it may not seem likely but you can actually place all 5s (with Flat Mates logic, limiting 1s, 5s and 9s), but also consider the high digits that need to appear in many circles, and the low digits that can only appear in a few. The diagonals are very powerful.
This Weeks Puzzle
Solution code: Digits from Row 7
Comments
on 3. July 2024, 15:08 by ViKingPrime
I almost missed the part about where 5s live, which would've been a shame as this may very well be the best of the series. Such a good use of every single constraint; love how the puzzle shifts gears every now and then, requiring you to think along different lines. Beautiful stuff.
Flinty: Thank you. This is definitely my favourite puzzle that I have made.
on 13. April 2024, 12:04 by Black_Doom
Simply brilliant :)
Flinty: Thank you BD :)
on 11. April 2024, 15:32 by Franjo
Again no need for any hints here. But this is a masterpiece, which I loved to solve. Thank you so much for setting this gem and sharing it.
on 11. April 2024, 00:23 by Flinty
Thank you so much for the kind comments. As goodcity has alluded, this has been my Magnum Opus Dutch Flat Mates, and has been in the works for months.
Also congrats goodcity on Numbered Rooms getting a ctc solve :)
on 10. April 2024, 22:23 by sujoyku
Thank you for this beautiful puzzle, Flinty! I love counting circles logic and the combination with the Dutch flat mates constraint was just gorgeous. Thank you for setting and sharing!
on 10. April 2024, 16:06 by goodcity
I know this one took long to create and I am glad you managed to set such a great puzzle !
on 10. April 2024, 12:56 by Flinty
Fixed the rules typos. Thanks. :)
on 10. April 2024, 12:50 by sorryimLate
Great puzzle! I love counting circles and this an amazingly clever combination of these rulesets. A nice challenge but not too hard. Thanks for sharing!
on 10. April 2024, 11:56 by marcmees
Q: the blue diagonals have a meaning?
