The New Sudoku Players' Forum

[ArkieTech]

Code: Select all

 *-----------*
 |...|...|..3|
 |4..|...|...|
 |..2|38.|.9.|
 |---+---+---|
 |6.7|...|45.|
 |...|.5.|...|
 |...|.37|..2|
 |---+---+---|
 |15.|8.3|...|
 |.6.|...|1.7|
 |...|6.1|.4.|
 *-----------*


Play/Print this puzzle online

[SteveG48]

Code: Select all

 *---------------------------------------------------*
 | 5    9-8  6    |e279  1    4    |ea27 ea78   3    |
 | 4    89   3    | 279  6   d29   | a257  1    58   |
 | 7    1    2    | 3    8    5    |  6    9    4    |
 *----------------+----------------+-----------------|
 | 6    3    7    | 29   29   8    |  4    5    1    |
 | 8    2    1    | 4    5    6    |  37   37   9    |
 | 9    4    5    | 1    3    7    |  8    6    2    |
 *----------------+----------------+-----------------|
 | 1    5    4    | 8    7    3    |  9    2    6    |
 | 23   6    89   | 5    4   c29   |  1    38   7    |
 |b23   7    89   | 6   b29   1    | b35   4    58   |
 *---------------------------------------------------*


(8=257)b3p124 - (5=239)r9c157 - 9r8c6 = r2c6 - (9=278)r1c478 => -8 r1c2 ; stte

[bat999]

Code: Select all

.--------------.---------------.---------------.
|  5    89  6  | 279  1    4   | 27    78   3  |
|  4   a89  3  | 279  6    2-9 | 257   1   a58 |
|  7    1   2  | 3    8    5   | 6     9    4  |
:--------------+---------------+---------------:
|  6    3   7  | 29   29   8   | 4     5    1  |
|  8    2   1  | 4    5    6   | 37    37   9  |
|  9    4   5  | 1    3    7   | 8     6    2  |
:--------------+---------------+---------------:
|  1    5   4  | 8    7    3   | 9     2    6  |
| c23   6   89 | 5    4   c29  | 1    c38   7  |
|  23   7   89 | 6    29   1   | 35    4   b58 |
'--------------'---------------'---------------'

(9=5)r2c29 - (5=8)r9c9 - (8=9)r8c168 => -9 r2c4; stte

[Marty R.]

Code: Select all

+----------+-----------+-----------+
| 5  89 6  | 279 1  4  | 27  78 3  |
| 4  89 3  | 279 6  29 | 257 1  58 |
| 7  1  2  | 3   8  5  | 6   9  4  |
+----------+-----------+-----------+
| 6  3  7  | 29  29 8  | 4   5  1  |
| 8  2  1  | 4   5  6  | 37  37 9  |
| 9  4  5  | 1   3  7  | 8   6  2  |
+----------+-----------+-----------+
| 1  5  4  | 8   7  3  | 9   2  6  |
| 23 6  89 | 5   4  29 | 1   38 7  |
| 23 7  89 | 6   29 1  | 35  4  58 |
+----------+-----------+-----------+


Play this puzzle online at the Daily Sudoku site

(8=9)r8c3-r8c6=r2c6-(9=8)r2c2-r1c2=8r1c8=> -8r8c8

[Leren]

Code: Select all

*-----------------------------------------------------*
| 5   d89   6     |c279  1    4     | 27  e78   3     |
| 4    89   3     | 279  6   b29    | 257  1    58    |
| 7    1    2     | 3    8    5     | 6    9    4     |
|-----------------+-----------------+-----------------|
| 6    3    7     | 29   29   8     | 4    5    1     |
| 8    2    1     | 4    5    6     | 37   37   9     |
| 9    4    5     | 1    3    7     | 8    6    2     |
|-----------------+-----------------+-----------------|
| 1    5    4     | 8    7    3     | 9    2    6     |
| 23   6   g8-9   | 5    4   a29    | 1   f38   7     |
| 23   7    89    | 6    29   1     | 35   4    58    |
*-----------------------------------------------------*

(9) r8c6 = r2c6 - r1c4 = (9-8) r1c2 = r1c8 - r8c8 = (8) r8c3 => - 9 r8c3; stte

Leren

[ArkieTech]

Code: Select all

 *--------------------------------------------------*
 | 5    89   6    | 279  1    4    | 27   78   3    |
 | 4   a89   3    | 279  6   a29   | 257  1   a58   |
 | 7    1    2    | 3    8    5    | 6    9    4    |
 |----------------+----------------+----------------|
 | 6    3    7    | 29   29   8    | 4    5    1    |
 | 8    2    1    | 4    5    6    | 37   37   9    |
 | 9    4    5    | 1    3    7    | 8    6    2    |
 |----------------+----------------+----------------|
 | 1    5    4    | 8    7    3    | 9    2    6    |
 | 23   6    89   | 5    4    9-2  | 1    38   7    |
 | 23   7   b89   | 6   b29   1    | 35   4   b58   |
 *--------------------------------------------------*
[(2=5)r2c269-(5=2)r9c259]-2r8c5; ste


[bat999]

The two-ALS chains are en vogue.

ArkieTech's from October 7
[(2=5)r2c269-(5=2)r9c259]-2r8c5; ste

Steve's from October 6
(4=23)r3c39 - (3=247)r124c7 => -4 r3c8 ; stte

Mine from October 5
(9=7)r3c1 - (7=9)r23479c4 => -9 r4c1; stte

blue's from October 4
(5=3)r1c267 - (3=5)r234c1 => r4c7<>5; stte

[Aldoredo]

Don't know how you notate this but there's a potential unique rectangle (on 2,7) at r12c4 and r12c7

The opposite corners r1c7 and r2c4 are strongly linked on 2,7 respectively within their row & column....

So, r1c7 cannot be 7 (and r2c4 cannot be 2) stte.

Or have I missed something?

[SteveG48]

Don't know how you notate this but there's a potential unique rectangle (on 2,7) at r12c4 and r12c7

The opposite corners r1c7 and r2c4 are strongly linked on 2,7 respectively within their row & column....

So, r1c7 cannot be 7 (and r2c4 cannot be 2) stte.

Or have I missed something?

Hello, Aldoredo. First, welcome aboard.

I see the strong link between 2r1c7 and 7r2c4, and I see how you conclude that r1c7 cannot be 7. However, I don't see the conclusion that r2c4 cannot be 2. I see it leaving you with a 2/9 pair in r2c46 and another in r24c4. You need both eliminations to solve the puzzle, so I don't think you're there yet.

[Aldoredo]

Thanks Steve and thanks for the welcome... fools rush in, etc. I wonder how many puzzles I've 'solved' this way

Now, with a 2 in r1c7, I see that the next step is straightforward, as we are left with a 'bug' at r2c4 (=9) stte.

I'll engage brain before posting next time. And if somebody can point me in the direction of a tutorial on the notation used here, I shall be eternally grateful.

Al

[bat999]

... a tutorial on the notation used here...

Hi
This would be a good place to start ---> http://sudopedia.enjoysudoku.com/Eureka.html
Then maybe open a new thread if you have any questions about it.