The New Sudoku Players' Forum

[ArkieTech]

Code: Select all

 *-----------*
 |5..|.9.|...|
 |.9.|..2|1..|
 |...|6..|..4|
 |---+---+---|
 |7..|.6.|.39|
 |..5|1.9|2..|
 |24.|.3.|..5|
 |---+---+---|
 |6..|..4|...|
 |..7|9..|.4.|
 |...|.5.|..3|
 *-----------*


Play/Print this puzzle online

[pjb]

Code: Select all

 5      b178     6      | 4      9     c178    | 3      278    278   
 4       9       3      | 5      78     2      | 1      678    678   
a18      1278    128    | 6      178    3      | 9      5      4     
------------------------+----------------------+---------------------
 7       18      18     | 2      6      5      | 4      3      9     
 3       6       5      | 1      4      9      | 2      78     78     
 2       4       9      | 78     3      78     | 6      1      5     
------------------------+----------------------+---------------------
 6       5       128    | 3      1278   4      | 78     9      12     
 1-8     3       7      | 9      128   d168    | 5      4      126   
 9       12      4      | 78     5     d16     | 78     26     3     


(8=1)r3c1 - r1c2 = r1c6 - (1=68)r89c6 => -8 r8c1; stte

Phil

[Leren]

Code: Select all

*-------------------------------------------*
| 5   e17-8 6   | 4  9    d178 | 3  278 278 |
| 4    9    3   | 5  78    2   | 1  678 678 |
|a8-1  1278 128 | 6  178   3   | 9  5   4   |
|---------------+--------------+------------|
| 7    18   18  | 2  6     5   | 4  3   9   |
| 3    6    5   | 1  4     9   | 2  78  78  |
| 2    4    9   | 78 3    d78  | 6  1   5   |
|---------------+--------------+------------|
| 6    5    128 | 3  1278  4   | 78 9   12  |
|b18   3    7   | 9  128  c168 | 5  4   126 |
| 9    12   4   | 78 5     16  | 78 26  3   |
*-------------------------------------------*

(8=1) r3c1 - (1=8) r8c1 - r8c6 = (78-1) r16c6 = (1) r1c2 => - 8 r1c2, - 1 r3c1; stte

Leren

<edit> Fixed faulty logic in the chain, Leren

[Marty R.]

Code: Select all

+-------------+-------------+------------+
| 5  178  6   | 4  9    178 | 3  278 278 |
| 4  9    3   | 5  78   2   | 1  678 678 |
| 18 1278 128 | 6  178  3   | 9  5   4   |
+-------------+-------------+------------+
| 7  18   18  | 2  6    5   | 4  3   9   |
| 3  6    5   | 1  4    9   | 2  78  78  |
| 2  4    9   | 78 3    78  | 6  1   5   |
+-------------+-------------+------------+
| 6  5    128 | 3  1278 4   | 78 9   12  |
| 18 3    7   | 9  128  168 | 5  4   126 |
| 9  12   4   | 78 5    16  | 78 26  3   |
+-------------+-------------+------------+


Play this puzzle online at the Daily Sudoku site

Kite (1) hinged box 7
1r3c1=r9c6
1r3c1-r3c5=r1c6-(1=68)r98c6-(8=12)r8c1,r9c2
1r9c6-(1=2)r9c2=> 2r9c2

[SteveG48]

Code: Select all

 *-----------------------------------------------------------*
 | 5     178   6     | 4     9    c178   | 3     278   278   |
 | 4     9     3     | 5     78    2     | 1     678   678   |
 |a18    1278  128   | 6    b178   3     | 9     5     4     |
 *-------------------+-------------------+-------------------|
 | 7     18    18    | 2     6     5     | 4     3     9     |
 | 3     6     5     | 1     4     9     | 2     78    78    |
 | 2     4     9     | 78    3     78    | 6     1     5     |
 *-------------------+-------------------+-------------------|
 | 6     5     128   | 3     1278  4     | 78    9     12    |
 | 1-8   3     7     | 9     128  d168   | 5     4     126   |
 | 9     12    4     | 78    5    d16    | 78    26    3     |
 *-----------------------------------------------------------*


(8=1)r3c1 - r3c5 = r1c6 - (1=68)r89c6 => -8 r8c1 ; stte

[Cenoman]

Code: Select all

 +--------------------+--------------------+-------------------+
 |  5   c178    6     |  4    9     b178   |  3    278   278   |
 |  4    9      3     |  5    78     2     |  1    678   678   |
 | d18   1278   128   |  6    178    3     |  9    5     4     |
 +--------------------+--------------------+-------------------+
 |  7    18     18    |  2    6      5     |  4    3     9     |
 |  3    6      5     |  1    4      9     |  2    78    78    |
 |  2    4      9     |  78   3     b78    |  6    1     5     |
 +--------------------+--------------------+-------------------+
 |  6    5      128   |  3    1278   4     |  78   9     12    |
 |  1-8  3      7     |  9    128   a168   |  5    4     126   |
 |  9    12     4     |  78   5      16    |  78   26    3     |
 +--------------------+--------------------+-------------------+

Almost hidden pair (78)r16c6
(8)r8c6 = (87-1)r16c6 = r1c2 - (1=8)r3c1 => -8 r8c1; stte

Cenoman

[Marty R.]

Code: Select all

 +--------------------+--------------------+-------------------+
 |  5   c178    6     |  4    9     b178   |  3    278   278   |
 |  4    9      3     |  5    78     2     |  1    678   678   |
 | d18   1278   128   |  6    178    3     |  9    5     4     |
 +--------------------+--------------------+-------------------+
 |  7    18     18    |  2    6      5     |  4    3     9     |
 |  3    6      5     |  1    4      9     |  2    78    78    |
 |  2    4      9     |  78   3     b78    |  6    1     5     |
 +--------------------+--------------------+-------------------+
 |  6    5      128   |  3    1278   4     |  78   9     12    |
 |  1-8  3      7     |  9    128   a168   |  5    4     126   |
 |  9    12     4     |  78   5      16    |  78   26    3     |
 +--------------------+--------------------+-------------------+

Almost hidden pair (78)r16c6
(8)r8c6 = (87-1)r16c6 = r1c2 - (1=8)r3c1 => -8 r8c1; stte

Cenoman

Cenoman,

Perhaps you can help me understand. To me, an Almost Hidden Pair solution would be when there is a common outcome if the pair is true and if the "fin" is true. I don't see where the chain reflects an Almost Hidden Pair. Sure, the 1st term of r8c6<>1 is a result of the pair being true but I don't see anything about what happens if the pair is not true. Having said that, I think your solution is clever but don't see it as Almost Hidden Pair solution.

[Cenoman]

To me, an Almost Hidden Pair solution would be when there is a common outcome if the pair is true and if the "fin" is true.

Marty, I have the same definition, and I guess it is met here:
The "fin" is 8r8c6
If the pair (78)r16c6 is true, then r1c6<>1, r1c2=1, r3c1=8, r8c1<>8
If the fin 8r8c6 is true, then r8c1<>8
r8c1<>8 is the common outcome.

Maybe could I have written it clearer this way:
(87)r16c6 - (1)r1c6 = r1c2 - (1=8)r3c1
(8)r8c6
=> -8 r8c1; stte

An alternative chain appending to the fin:
(78)r16c6
(8)r8c6 - (8=1)r8c1 - r9c2 = (1)r9c6
=>1 r1c6; stte

Cenoman

[Marty R.]

To me, an Almost Hidden Pair solution would be when there is a common outcome if the pair is true and if the "fin" is true.

Marty, I have the same definition, and I guess it is met here:
The "fin" is 8r8c6
If the pair (78)r16c6 is true, then r1c6<>1, r1c2=1, r3c1=8, r8c1<>8
If the fin 8r8c6 is true, then r8c1<>8
r8c1<>8 is the common outcome.

Maybe could I have written it clearer this way:
(87)r16c6 - (1)r1c6 = r1c2 - (1=8)r3c1
(8)r8c6
=> -8 r8c1; stte

An alternative chain appending to the fin:
(78)r16c6
(8)r8c6 - (8=1)r8c1 - r9c2 = (1)r9c6
=>1 r1c6; stte

Cenoman

Cenoman,

I don't want this exchange to go on forever. But we differ on the fin . I think the fin is 1 r1c6 since that precludes a 78 pair. Based on that, if the pair is true then r1c6<>1 and if false r1c6=1 and those can't yield a common outcome. ???

[Cenoman]

I don't want this exchange to go on forever.

Nor do I

But we differ on the fin . I think the fin is 1 r1c6 since that precludes a 78 pair. Based on that, if the pair is true then r1c6<>1 and if false r1c6=1 and those can't yield a common outcome. ???

Marty,

The term of fin is used in fish patterns. Here, you and I have used it by analogy, but with " ", which is justified since the pattern (78)r16c6 is a pair and not a fish (not even a 1-fish): it cannot work without the 7's.
To me, the "fin" is rather 8r6c6, once more by analogy to fish-patterns whose fins are candidates of the same digit as the fish itself.

You focus on the strong link (78=1)r16c6 whereas I focus on the weak link (78-1)r16c6. Both links are true ! Cells r16c6 contains an ALS as well as an AHS (particular case of ALS's with two and only two unlocked digits)
If I had used 1r1c6 as the "fin", I would have called the pattern "Almost naked pair". It is feasible and also yields a killing common outcome (-1 r3c1):
(78)r16c6 - (1)r1c6 = r3c5 - r3c123 = (1)r1c2
(1)r1c6 - (1=8)r89c6 - (8=1)r8c1
=> -1 r3c1; stte
Note the use of both links of 1r1c6 to the pair (78)r16c6 but chains are a bit longer...

Best regards, Cenoman

[Marty R.]

Cenoman,

Thanks I understand and see what you're doing. Thankfully, this conversation has now been put to bed.

Regards,
Marty