Seven Quads for Seven Corners
(Published on 24. June 2022, 19:44 by mith)
by Philip Newman
Normal sudoku rules apply.
Digits in corner circles must appear in the surrounding four cells, in some order.
Play on f-puzzles
Play on CTC App
This puzzle is from a series of "nerd snipe" constructions, originally posted on the CTC fan discord server. In Februrary, I was able to find a puzzle with only eight quadruples (Cornucopia), but suspected seven might be possible. When jovi_al posted Road Trip, using the weaker constraint of 2x2 cages instead of quadruples, I was inspired to revisit and managed to construct this. It has a similar layout to Road Trip - six of the quadruples are in the same places as their killer cage counterparts - but the two puzzles solve quite differently. Check out Road Trip if you haven't already, it's a bit harder but has a gorgeous solve path!
It is not currently known whether this is the minimum for the quadruples constraint, nor whether seven 2x2 killer cages is possible.
Looking for something harder than this? My previous nerd snipe puzzle, Snek is Friend, only has a few solves!
Solution code: Row 8, followed by column 8
Comments
on 28. December 2022, 02:00 by RussKozerski
This puzzle presented the smoothest solve path I've ever experienced in a sudoku. I kept thinking I was about to hit a snag. But one solution led to the next, which led to the next, and so on. Very very nice.
on 18. September 2022, 14:31 by profanat
Nice and easy
on 23. July 2022, 00:45 by Schlopsi
Enjoyed this one! Fun when you want to start with Quadruples.
on 23. July 2022, 00:15 by Blobz
Very approachable. Never felt stuck along the solution path.
on 30. June 2022, 19:29 by sacklunch
Great puzzle, very enjoyable!
on 26. June 2022, 21:12 by josemadre
Clever and approachable!
on 25. June 2022, 06:24 by Dermerlin
nice puzzle, thx
For me (not an expert) it felt like 2 or even 3 stars
on 25. June 2022, 02:17 by Calvinball
Wow, such a wonderful solve path all the way throughout the puzzle. A perfect example that beautiful puzzles don't need to be blistering difficult.
on 24. June 2022, 23:59 by TheCaretaker
I usually struggle with these puzzles, but this was a nice one. Just hard enough for me to manage.
on 24. June 2022, 22:01 by Playmaker6174
Very smooth solve and what a wonderful discovery for such minimal conditions ;)
