Irregular Sudoku [New Example]

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Is this suitable for a Sudoku competition?

Yes
8
67%
Maybe
3
25%
No
1
8%
 
Total votes: 12

detuned
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Irregular Sudoku [New Example]

Post by detuned » Sun 30 Dec, 2018 2:39 pm

example-irregular.png
example-irregular.png (20.75 KiB) Viewed 1197 times
In theory Irregular Sudoku can be defined so that the marked regions entirely overlap the rows or columns of the grid. This is not quite the case for this example, however a lot (not all) of the solving logic required for this puzzle effectively ignores the 3rd regional constraint.

Fred76
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Re: Irregular Sudoku [New Example]

Post by Fred76 » Sat 05 Jan, 2019 5:28 pm

It is a nice example.
I already thought about limits for irregular sudoku, more in term of minimum number of regions. Here I mean regions by connected subset of cells that are distinct from rows and columns. Some irregulars have only 7 or 8 such regions (1 or 2 regions are indeed rows or columns) and I have no problem with that. I would have problem if the number of regions become too small...
Your example is very good because we have here 8 regions (thus it could be ok with my consideration above), but only 8 cells constrained by these regions, meaning it is factually closer to a latin square.
I answered "maybe", because I think some limits have to be decided concerning the number of regions (disctincts from rows and columns), but I don't see with which argument I could say your example is not a sudoku.

Fred

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