The New Sudoku Players' Forum

[tso]

I stumbled upon an interesting variant called Maxi Sudoku that seems obvious but had never occured to me before. I haven't taken the time to solve one yet, but I think it's a great idea. Ignoring the blank boxes, there are a total of 135 cells in the puzzle, making it larger than the standard 9x9 Sudoku but smaller than two 9x9s with a single box overlap (153 cells) or a 12x12 puzzle (144 cells). This seems like a pefect 'next larger' size to work on, especially since it doesn't need more than 9 symbols. Here's the sample puzzle:

Code: Select all

 . . 1 |-blank-|-blank-| . 8 4 | 2 . 9
 . 2 6 |-blank-|-blank-| 9 . . | . . .
 8 . . |-blank-|-blank-| 5 . . | 3 . .
-------+-------+-------+-------+-------
 . . 9 | . . . |-blank-|-blank-| 5 . 8
 . . . | . . . |-blank-|-blank-| . . .
 . . . | 4 . . |-blank-|-blank-| . . .
-------+-------+-------+-------+-------
 . 7 . | . . . | . . . |-blank-|-blank-
 6 . . | . 1 . | . . . |-blank-|-blank-
 . . 4 | . 6 . | 3 5 9 |-blank-|-blank-
-------+-------+-------+-------+-------
-blank-| . . 7 | . . . | . . . |-blank-
-blank-| 1 . . | . . 6 | . . . |-blank-
-blank-| . . 8 | 2 . 5 | . 9 1 |-blank-
-------+-------+-------+-------+-------
-blank-|-blank-| 9 . 7 | . . . | . . .
-blank-|-blank-| 6 2 . | . . . | . 3 .
-blank-|-blank-| . 4 . | 6 2 . | 9 . .

The -blank- boxes remain blank. The other 15 boxes, as well as all 15 rows and columns must contain 1 though 9. (Any other arrangement of 25 boxes will work as long as 2 blank boxes are in each row and column of boxes.)


Though the site doesn't mention it, one might construct a 12 by 12 puzzle in a similar fashion -- 16 boxes, 4 blanked out:

Code: Select all

-blank-| . . . | . . . | . . .
-blank-| . . . | . . . | . . .
-blank-| . . . | . . . | . . .
-------+-------+-------+-------
 . . . |-blank-| . . . | . . .
 . . . |-blank-| . . . | . . .
 . . . |-blank-| . . . | . . .
-------+-------+-------+-------
 . . . | . . . |-blank-| . . .
 . . . | . . . |-blank-| . . .
 . . . | . . . |-blank-| . . .
-------+-------+-------+-------
 . . . | . . . | . . . |-blank-
 . . . | . . . | . . . |-blank-
 . . . | . . . | . . . |-blank-

... or ...

Code: Select all

 1 2 3 |-blank-| 4 5 6 | 7 8 9
 9 7 8 |-blank-| 3 1 2 | 6 4 5
 5 6 4 |-blank-| 8 9 7 | 2 3 1
-------+-------+-------+-------
 4 5 6 | 1 2 3 | 7 8 9 |-blank-
 3 1 2 | 9 7 8 | 6 4 5 |-blank-
 8 9 7 | 5 6 4 | 2 3 1 |-blank-
-------+-------+-------+-------
-blank-| 7 8 9 | 1 2 3 | 4 5 6
-blank-| 6 4 5 | 9 7 8 | 3 1 2
-blank-| 2 3 1 | 5 6 4 | 8 9 7
-------+-------+-------+-------
 7 8 9 | 4 5 6 |-blank-| 1 2 3
 6 4 5 | 3 1 2 |-blank-| 9 7 8
 2 3 1 | 8 9 7 |-blank-| 5 6 4

... or any other arrangement with one blank box in each row and column of boxes. The idea can be extended to 36 boxes with half blanked out, etc.