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Is this a new technique?

 
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Bud



Joined: 06 May 2010
Posts: 47
Location: Tampa, Florida

PostPosted: Sun Jul 11, 2010 7:49 pm    Post subject: Is this a new technique? Reply with quote

Recently, I found the 3-digit, 4-cell pattern labeled ABCD in this puzzle. To understand how this works, consider the cell A =67 as the pivot cell as in a wing.
(7)A=(4)B and (6)A-(6)C=(6)D.
Therefore B=4 or D=6 => D<>4 which solves the puzzle. Using this approach of a pivot cell, I have been able to find a lot of S-Wings in my puzzles and both the 6 AIC and the or cell elimination resemble an S=Wing. But the S-Wing has only 2 digits and 5 cells. If anyone has seen this pattern before, please let me know what it is called. If it is new what should it be called?

3-Digit 4-Cell Pattern Example
Code:

 |-------------------+--------------------+--------------------|
 |    6   125     8  |    3    57    25   |  279     4    179  |
 |  234   234   347  | 24678    1     9   | 2678     5    378  |
 | 12349 12345 13479 | 24678 4578  2456   | 2678   138   1378  |
 |-------------------+--------------------+--------------------|
 |  347    34     2  |   67A   35     8   |    1     9    456C |
 | 1348     9     6  |   14     2    35   |   58     7    458  |
 |  178    18     5  |    9    47B  146   |    3     2   -468D |
 |-------------------+--------------------+--------------------|
 | 123489 12348 1349 | 1248  3489  1234   |   57     6     57  |
 | 12348    7   134  |    5     6  1234   |   89   138   1389  |
 |    5     6   139  |   18   389     7   |    4   138      2  |
 |-------------------+--------------------+--------------------|


This puzzle is the July 10, 2010 Tough at sudoku.com.au. I used a 35 ALS-XZ (R14C7-R4C25) to reach this point in the puzzle.
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ronk



Joined: 07 May 2006
Posts: 397

PostPosted: Sun Jul 11, 2010 11:15 pm    Post subject: Re: Is this a new technique? Reply with quote

Bud wrote:
Therefore B=4 or D=6 => D<>4 which solves the puzzle. Using this approach of a pivot cell, I have been able to find a lot of S-Wings in my puzzles and both the 6 AIC and the or cell elimination resemble an S=Wing. But the S-Wing has only 2 digits and 5 cells. If anyone has seen this pattern before, please let me know what it is called. If it is new what should it be called?

3-Digit 4-Cell Pattern Example
Code:

 |-------------------+--------------------+--------------------|
 |    6   125     8  |    3    57    25   |  279     4    179  |
 |  234   234   347  | 24678    1     9   | 2678     5    378  |
 | 12349 12345 13479 | 24678 4578  2456   | 2678   138   1378  |
 |-------------------+--------------------+--------------------|
 |  347    34     2  |   67A   35     8   |    1     9    456C |
 | 1348     9     6  |   14     2    35   |   58     7    458  |
 |  178    18     5  |    9    47B  146   |    3     2   -468D |
 |-------------------+--------------------+--------------------|
 | 123489 12348 1349 | 1248  3489  1234   |   57     6     57  |
 | 12348    7   134  |    5     6  1234   |   89   138   1389  |
 |    5     6   139  |   18   389     7   |    4   138      2  |
 |-------------------+--------------------+--------------------|

The pattern is known to some as a hybrid-wing, but the name is not exclusive to this pattern.
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Bud



Joined: 06 May 2010
Posts: 47
Location: Tampa, Florida

PostPosted: Sun Jul 11, 2010 11:38 pm    Post subject: Reply with quote

Thanks Ronk. I think I have seen rectangular patterns called that. I like the name.
Bud
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