Dutch Flat Mates: Multiple Lines
(Published on 24. June 2026, 07:00 by marty_sears)
Rules:
Normal sudoku rules apply.
Every 5 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.
For two adjacent digits along a coloured line, dividing one by the other gives an exact integer (one is a multiple of the other.)
Solution code: Column 3 reading downwards
Comments
on 13. July 2026, 17:29 by ThymePass
RAR extracted smoothly. Thank you :)
on 13. July 2026, 15:51 by ragakeet
Ok, so I oh so stupidly misread the Dutch Flat Mate rule and thought the 1s go below the 5s and the 9s above, yet I believe with my butchered rules this too solves uniquely, and satisfyingly. I was so confused when the software declined my solution.
Not sure if this was intentional but it might have something to do with the symmetry of the puzzle.
Edit: My suspicions were correct, all I had to do was rotate my solution 180 degrees to get the correct solution. This was probably my strangest sudoku solve yet lol
Marty: yes haha. The DFM rule is the only thing that disambiguates the symmetry. So if you invert the rule, you invert the solution!
on 9. July 2026, 08:34 by Piatato
Smooth!
on 9. July 2026, 05:31 by antiknight
Great!
on 7. July 2026, 17:42 by yuripuppies
What a lovely, accessible puzzle! I found the break-in immediately and whenever I got stuck using one half of the ruleset, the other half of it came to the rescue
on 7. July 2026, 06:30 by Ratfinkz
Loved this! Beautiful puzzle, thank you!
on 30. June 2026, 00:20 by firespire
I used to love doing Dutch Flat Mates but as time went on they got more mathsy than my skill ability.
I'm able to work out if one number is divisable by another.
So pleased to complete this one, I really missed solving them. Thank You.
on 29. June 2026, 18:15 by Klausku
Very nice puzzle. I like the symmetry, even the given 8 contributes. Thanks!
on 25. June 2026, 11:31 by mscha
Nice one!
Seemed almost impossible, but after finding the right clues, it basically solved itself.
on 25. June 2026, 01:08 by Atticus837
Very proud of myself for actually remembering the Dutch flatmates constraint within the first couple of minutes for once!
on 24. June 2026, 23:45 by damo_89
There are indeed multiple lines, gg :)
on 24. June 2026, 23:16 by harwiltz
What an amazing puzzle. Looks utterly hopeless at first glance, but the logic is beautiful.
on 24. June 2026, 23:08 by Snaques
This was another one that initially felt impossible and had no idea where to even begin. After a couple of minutes it started to clarify and in the end was just a wonderful puzzle.
on 24. June 2026, 13:49 by Flinty
Thank you my friend, lovely puzzle and layout.
on 24. June 2026, 13:38 by Vikkz
Amazing!
on 24. June 2026, 12:04 by Franjo
Thank you very much for creating and sharing another fantastic DFM-puzzle. The symmetry of the Factor Lines is incredible!
