Sudoku Bachelor
Inspiration for this type comes from 真笑(洪卫华).
Solve online in Penpa+ (thx Henrypijames!) or F-Puzzles (thx snowyegret!)
Apply classic sudoku rules.
In all cases where in an area of 2x2 exactly one pair of consecutive digits is present, a circle is placed on the intersection of the grid lines of that area. The digits in the circle have to be placed in that area, but are not part of the consecutive pair in that area. If for example 4-6-7-9 are placed in a 2x2 area, 4-9 is in the circle. The combinations 1-2-3-8, 1-2-2-8 and 2-3-5-6 don’t get a circle. If there is an equal-sign in the circle, the two digits that don’t belong to the pair are the same. For example: 3-4-9-9.
Solution code: Row 1, followed by column 8.
on 4. September 2022, 07:46 by Richard
Added links and tag for online solving. Thx Henrypijames and snowyegret!
on 12. August 2022, 14:34 by snowyegret
https://f-puzzles.com/?id=2ojdy588
on 21. January 2022, 00:49 by Nick Smirnov
@Richard, but why is this sudoku called Bachelor? :D
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@Nick: I think because there is exactly one 'pair' and two 'bachelors' around each circle.
on 15. April 2021, 21:45 by Richard
@Henry: my apologies; the puzzle in your link is correct; the puzzle in Mavericks link is missing the equal sign. :-)
on 15. April 2021, 06:33 by cdwg2000
Thank you Richard for further clarification of the rules! There is a slightly more difficult problem here, maybe you can try it if you are interested: https://logic-masters.de/Raetselportal/Raetsel/zeigen.php?id=0004ZJ
on 15. April 2021, 06:25 by indecisive1994
Seemed very daunting at first, but it went very smoothly after getting into it. Very interesting idea, one of my favorite puzzles I've solved!
on 14. April 2021, 16:53 by hamslice
I thought I'd lost the plot last night!
Regardless of the setting issues, the logic was nice to wind down with before bed. :)
on 14. April 2021, 16:17 by henrypijames
In the Penpa+ link I provided, there is already (and always has been) a circle with an equal sign between box 3 and 6. Should there be a second such circle?
on 14. April 2021, 12:48 by marcmees
negative constraint almost not needed.
thanks for this weekly piece of joy.
on 14. April 2021, 11:48 by cdwg2000
As far as I know, this rule set requires patience and negative constraints apply. If the marked circled numbers are A and B, all the numbers ABCD in the four squares of the circle meet: 1. A and B are non-continuous numbers; 2. C and D are continuous numbers; 3. C and D are not continuous with A or B; 4. ABCD are not equal. If the marked circle “=” sign, there are numbers abcd: 1. Two numbers must be equal; 2. The other two numbers must be continuous; 3. The continuous number and the third number must not be continuous.
on 14. April 2021, 11:09 by Richard
@Henry: thanks for the link. And the previous links too.
@Henry: in the link is missing a dot with an equal-sign. Can you still add that?
on 14. April 2021, 11:06 by Richard
@Henry: 1667 does not qualify for a circle. It is very similar to the example 1228 as written in the instructions.
on 14. April 2021, 11:05 by henrypijames
Clarification of rules: Does 1667 qualify for a circle? It could be interpreted as either one or two consecutive pairs.
Edit: Yes, sorry I didn't study the rules carefully enough. The 1228 example addressed my question already.
on 14. April 2021, 10:46 by henrypijames
Penpa+: https://git.io/JOsvx
on 14. April 2021, 04:28 by cdwg2000
@Richard
Now it works fine.
on 14. April 2021, 04:09 by Richard
The description of the solution code was invalid, so it was changed.
@cdwg2000: you are right; one circle was missing. I missed that. My apologies!
It is now added.