The New Sudoku Players' Forum

[dmarsh]

I'm looking for a suggestion on the next move to solve this puzzle. Here is where I am:

Code:
9 4 6 ! 1 . 8 ! 2 . .
2 5 7 ! . . . ! . . .
. . 3 ! 7 . 2 ! 6 . .
------------------------
5 . 4 ! 6 . . ! . . .
6 . 8 ! 2 . 5 ! 4 . 9
. . 2 ! . . 7 ! 5 . 6
------------------------
. . 1 ! 3 . . ! 9 . .
. . 5 ! . . . ! 7 3 1
. . 9 ! 5 . 1 ! 8 6 .

Thanks, David

[daj95376]

I'm looking for a suggestion on the next move to solve this puzzle.

Code: Select all

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


It's difficult to know how far you've advanced with the information you provided. Assuming that it's only to complete Naked and Hidden Singles, then your next move might be a Naked Pair in [r3].

[dmarsh]

9 4 6 | 1 35 8 | 2 57 357
2 5 7 | 49 3469 3469 | 13 1489 348
18 18 3 | 7 459 2 | 6 459 45
---------------------------------------------------------
5 1379 4 | 6 1389 39 | 13 1278 2378
6 137 8 | 2 13 5 | 4 17 9
13 139 2 | 489 13489 7 | 5 18 6
-----------------------------------------------------------
478 268 1| 3 24678 46 | 9 245 245
48 268 5| 489 24689 469| 7 3 1
347 23 9| 5 247 1 | 8 6 24

Thanks - I have now included the pencil marks above to show where I have got to. I have the naked pair in r3 - what next ?

[daj95376]

The Naked Pair exposed a Naked Triple in [c9]. You get to find it and the Locked Candidate (1) afterwards.

Code: Select all

+-----------------------------------------------------------------------------+
|  9       4       6      |  1       35      8      |  2       57      357    |
|  2       5       7      |  49      3469    3469   |  13      1489    348    |
|  18      18      3      |  7       459     2      |  6       459     45     |
|-------------------------+-------------------------+-------------------------|
|  5       1379    4      |  6       1389    39     |  13      1278    2378   |
|  6       137     8      |  2       13      5      |  4       17      9      |
|  13      139     2      |  489     13489   7      |  5       18      6      |
|-------------------------+-------------------------+-------------------------|
|  478     268     1      |  3       24678   46     |  9       245     245    |
|  48      268     5      |  489     24689   469    |  7       3       1      |
|  347     23      9      |  5       247     1      |  8       6       24     |
+-----------------------------------------------------------------------------+


[dmarsh]

Thanks for that - I have eliminated the 2 from r3c9 i.e. r3c8 is a 2

The only thing I didn't understand was your Locked Candidate (1) - please explain, thanks

[dmarsh]

I think I have finally got there - 3 is a locked candidate in r4 c7 and r4 c9, therefore r4 c6 must be a 9

[Pat]

2.73 is a puzzle which i had once posted in the "ulterior" topic
which tells you that it can be solved by box-to-line exclusions ( + "hidden singles" )

Code: Select all

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



after "hidden singles" --

Code: Select all

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



-- the 3 for box 6 must be in row 4

leaving a "hidden single" 3 in column 6