The New Sudoku Players' Forum

[Bigtone53]

This sounds like you are not aware of the restrictions to all uniqueness techniques for killer. For instance in KSO Weekly 120, one cannot use UR for r12c14, nor any other rectangle with r12c1 because r12c1 are in two different cages and therefore do not form a valid dealy cycle.

I do understand this. I do not have 120 in front of me now but from memory there was a 10 in r1c78 which is 2/8 in some order. 3 rows lower down there is a cage where the c78 squares also turn out to total 10. Uniqueness says that they cannot be 2/8.

[Jean-Christophe]

That should be OK, as long as the UR fall into two cages, each with 2 cells of the UR.

However, I do not see any other pair of cells in URs with r1c78 which add up to 10: r4c78 = [72] = 9; r5c78 = [65] = 11; r9c78 = [53] = 8.

r6c78 = [19] = 10, but r16c78 does not form a UR. The only UR with r6c78 is r67c78.

Code: Select all

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

[/code]

[Bigtone53]

It was certainly part of my solving process that r4 c78 could not be 8/2, given r1 c78, and that as a result, at least one of 2 and 8 was elsewhere on r4. If that is what did it for me, why the problem?

[Jean-Christophe]

No problem. I just want to understand the logic you followed.

Pls do not take this as a personal offence. I also wanted to remind other members the UR limitations imposed by killers.

[Bigtone53]

Jean-Christophe,

Np problem at all . We are (nearly) all here to learn!

[Princess Amy]

My favorites are non-consecutive, and I like consecutives too if that's all I can find.