The New Sudoku Players' Forum

[5krunner]

Can anyone help with a next move on the following puzzle:

Here's where I am:

Code: Select all

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


Here's my pencil marks, which I hope are correct:

Code: Select all

267   79     8    | 3     69     469   | 1     246    5
236   4      236  | 7     5      1     | 9     268    368
1     39     5    | 4689  2      4689  | 34    7      3468
------------------+--------------------+-------------------
67    8      4    | 69    1679   3     | 56    156    2
5     1      2367 | 468   678    2468  | 34    9      3467
9     37     2367 | 5     167    246   | 8     146    13467
------------------+--------------------+-------------------
37    2      37   | 1     4      68    | 56    568    9
4     5      1    | 689   689    7     | 2     3      68
8     6      9    | 2     3      5     | 7     14     14


Thanks!!!

[daj95376]

You need to examine 2s and 8s for Locked Candidates (1).

[Edited: added] There are two types of Locked Candidates -- (1) and (2). These techniques have other names as well.

[5krunner]

Thanks for the advice ... when you say (1) do you mean box 1? Or are you referring to a column or row? Thanks again. Jay.

[MCC]

Look at row 2 and the number 8.

Look at box 4 and the number 2.


MCC

[5krunner]

MCC, I've applied your comments and get this ...

Code: Select all

267   79     8    | 3     69     469   | 1     246    5
236   4      36   | 7     5      1     | 9     268    368
1     39     5    | 4689  2      4689  | 34    7      346
------------------+--------------------+-------------------
67    8      4    | 69    1679   3     | 56    156    2
5     1      2367 | 468   678    2468  | 34    9      3467
9     37     2367 | 5     167    246   | 8     146    13467
------------------+--------------------+-------------------
37    2      37   | 1     4      68    | 56    568    9
4     5      1    | 689   689    7     | 2     3      68
8     6      9    | 2     3      5     | 7     14     14


This seems to take me a step forward ... I'm probably being obtuse but not sure what's next. Thanks again. Jay.

[udosuk]

Look at the top block in the middle (nonet 2/n2). Only the 3 right cells (r123c6) contain the candidate 9 on c6. Therefore all other cells in n2 (r123c45) cannot have 9. As a direct result r1c5 must be 6...

[MCC]

As well as using locked candidate on 9 in c6 to remove the other 9's in box 2 as udosuk as pointed out, you could also use an x-wing in 9's r4c45 and r8c45 (the 9*'s) to remove the same two 9's in box 2.

Code: Select all

267   79     8    | 3     69     469   | 1     246    5
236   4      36   | 7     5      1     | 9     268    368
1     39     5    | 4689  2      4689  | 34    7      346
------------------+--------------------+-------------------
67    8      4    | 69*   1679*  3     | 56    156    2
5     1      2367 | 468   678    2468  | 34    9      3467
9     37     2367 | 5     167    246   | 8     146    13467
------------------+--------------------+-------------------
37    2      37   | 1     4      68    | 56    568    9
4     5      1    | 689*  689*   7     | 2     3      68
8     6      9    | 2     3      5     | 7     14     14

MCC

[5krunner]

Udosuk, After your suggestion on the 9's in c6, everything fell into place very quickly! Thank you for that! Jay.

[Cec]

You need to examine 2s and 8s for Locked Candidates (1)........ There are two types of Locked Candidates -- (1) and (2). These techniques have other names as well.

Thanks for the advice ... when you say (1) do you mean box 1? Or are you referring to a column or row? Thanks again. Jay.

Hi 5krunner,
To add to the above help I'm assuming you were asking about "Locked Candidates (1)" and not a box, row or column. If that was the case then a good description for identifying "Locked Candidates (1) and (2) can be found by clicking on Here

Cec

[Litfev]

Too early...

[Cec]

Too early...

Just curious.. what do you mean by "Too early" ?

Cec