The New Sudoku Players' Forum

[mith]

Code: Select all

+-------+-------+-------+
| . . . | . . . | . . . |
| . 9 . | 1 . 7 | . 8 . |
| . . 8 | . 3 . | 9 . . |
+-------+-------+-------+
| . 1 . | 9 . 6 | . 3 . |
| . . 9 | . 5 . | 8 . . |
| . 6 . | 3 . 8 | . 7 . |
+-------+-------+-------+
| . . 4 | . 8 . | 3 . . |
| . 7 . | 6 . 3 | . 9 . |
| . . . | . . . | . . . |
+-------+-------+-------+
..........9.1.7.8...8.3.9...1.9.6.3...9.5.8...6.3.8.7...4.8.3...7.6.3.9..........

[edit2]fixed![/edit]

[urhegyi]

Code: Select all

+-------+-------+-------+
| . . . | . . . | . . . |
| . 9 . | 1 . 7 | . 8 . |
| . . 8 | . 3 . | 9 . . |
+-------+-------+-------+
| . 1 . | 9 . 6 | . 3 . |
| . . 9 | . 5 . | 8 . . |
| . 6 . | 3 . 8 | . 7 . |
+-------+-------+-------+
| . . 4 | . 8 . | 2 . . |
| . 7 . | 6 . 3 | . 9 . |
| . . . | . . . | . . . |
+-------+-------+-------+
..........9.1.7.8...8.3.9...1.9.6.3...9.5.8...6.3.8.7...4.8.2...7.6.3.9..........

[edit]had some digits swapped, fixed for thematic reasons[/edit]

We have a little problem. This sudoku has no solution.
A possible fix is thisone:

Code: Select all

..........9.1.7.8...8.3.9...1.9.6.3...9.158...6.3.8.7...4.8.2...7.6.3.9..........

Or an even harder one:

Code: Select all

..........9.1.7.8...8.3.9...1.9.6.3...9..58...6.3.8.7...4.8.2...7.6.3.9..........

Or just remove the 3 from R6C4:

Code: Select all

..........9.1.7.8...8.3.9...1.9.6.3...9.5.8...6...8.7...4.8.2...7.6.3.9..........

It has now 24 clues, which I prefer from the 3 proposed fixes. And it didn't change any digit, just removed one.
and here you can also remove the 8 at R2C8, so it has 23 clues.

Code: Select all

..........9.1.7.....8.3.9...1.9.6.3...9.5.8...6...8.7...4.8.2...7.6.3.9..........

[mith]

Oops, in trying to fix it the first time I had a typo. It's fixed now.

[urhegyi]

Oops, in trying to fix it the first time I had a typo. It's fixed now.

BTW The fixed version still has the posibility to remove the 3 from R6C4, so it has only 24 clues.

[mith]

Yes, I'm aware. It's minimal for the symmetry class. (Removing r6c4 still doesn't make it minimal, you can remove r2c8 as well.)

This puzzle is equivalent as far as the solve path goes (and minimal), removing r2c8 and r6c6:

Code: Select all

..........9.1.7.....8.3.9...1.9.6.3...9.5.8...6.3...7...4.8.3...7.6.3.9..........

But if you want a more difficult (and less thematic) puzzle, removing the 3 is the way to go:

Code: Select all

..........9.1.7.....8.3.9...1.9.6.3...9.5.8...6...8.7...4.8.3...7.6.3.9..........

[pjb]

4x2 MSLS at r2468 c57
Links: 6r2 7r4 1r6 24c5 245c7
12 Eliminations: -24 r1c5, -245 r1c7, -24 r9c5, -245 r9c7, -6 r2c139, -7 r4c3 => btte

Code: Select all

 1234567 2345    123567 | 8      69-24  2459   | 167-245 12456  1234567
 2345-6  9       235-6  | 1      246*   7      | 2456*   8      2345-6 
 167     245     8      | 245    3      245    | 9       16     167   
------------------------+----------------------+----------------------
 8       1       25-7   | 9      247*   6      | 245*    3      245   
 2347    234     9      | 247    5      124    | 8       1246   1246   
 245     6       25     | 3      124*   8      | 1245*   7      9     
------------------------+----------------------+----------------------
 69      25      4      | 257    8      1259   | 3       1256   12567 
 125     7       125    | 6      24*    3      | 245*    9      8     
 369     8       36     | 2457   179-24 12459  | 167-245 12456  124567


Phil