The New Sudoku Players' Forum

[sfddoc]

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

8 - - 2 - - - - -
6 - 7 - - - 3 - 4
- - - - - 3 - - 8

- - - - 5 7 8 - -
- 7 8 3 2 - - 6 5
- - - 8 4 - 7 3 2

[CathyW]

Assuming your candidate list is as follows (it does help if you let us know your candidates as well!):

Code: Select all

 *-----------*
 |394|165|287|
 |762|...|513|
 |185|732|...|
 |---+---+---|
 |8..|2..|...|
 |6.7|...|3.4|
 |...|..3|..8|
 |---+---+---|
 |...|.57|8..|
 |.78|32.|.65|
 |...|84.|732|
 *-----------*

 
 *-----------------------------------------------------------*
 | 3     9     4     | 1     6     5     | 2     8     7     |
 | 7     6     2     | 49    89    489   | 5     1     3     |
 | 1     8     5     | 7     3     2     | 469   49    69    |
 |-------------------+-------------------+-------------------|
 | 8     1345  139   | 2     179   1469  | 169   579   169   |
 | 6     125   7     | 59    189   189   | 3     259   4     |
 | 2459  1245  19    | 4569  179   3     | 169   2579  8     |
 |-------------------+-------------------+-------------------|
 | 249   1234  1369  | 69    5     7     | 8     49    19    |
 | 49    7     8     | 3     2     19    | 149   6     5     |
 | 59    15    169   | 8     4     169   | 7     3     2     |
 *-----------------------------------------------------------*


Naked pair {49} in column 8.
Followed by locked candidates (9s) in box 5.
Followed by another naked pair {17} in box 5.
The rest is singles.

[sfddoc]

cathy w, thanx for attempting to help me, i do appreciate it, but i need more help. i see the naked pairs in column 8 but it doesn,t seem to help me more except to eliminate 9s in box 6, column 8.

I don,t understand what you mean by locked candidates (9s) in box 5 - please help.

I don,t see 17 as naked pair in box 5 since i can,t get rid of the 1 as a candidate in row5, column 5.

thanx again for your help, i do want to solve this one.

[sfddoc]

cathy w, you are the best, now i see.

only been doing these a few months and never before had to use the concept of locked candidates type 2. i do get it now and appreciate your help so much. thanx again.

[CathyW]

Glad you figured it out

[Hud]

I don't see or understand the locked 9s in box 5, but there's a nice naked quad, 1789 in there that seems to help out a lot.

[tarek]

I don't see or understand the locked 9s in box .

Look at the 9s in box 5, then look at the 9s in row 5, ALL the 9s in row 5 are actually also in box 5.

There must be a 9 in row 5, so that means that those 9s in row5 are LOCKED and you can safely eliminate all other 9s in box 5 that are not in row 5 as the 9 HAS TO BE in row 5 eventually.

Tarek

[Hud]

I see now. I was looking at the candidates before removing the 9 due to the naked pair 49 earlier.