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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Sat Oct 13, 2007 11:24 am    Post subject: Sat Oct 13 DB |   |  
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				| Here is the Oct 13 DB as in the St. Louis paper. 
 I had to use strong pairs as pincers (coloring?) three times to solve it.
 
 Earl
 
 PS  There is also an x-y wing based at R7C7 which solves it.
 
 
  	  | Code: |  	  | +-------+-------+-------+
 | . . . | 8 . . | . . 7 |
 | 4 . . | . 7 . | 5 . . |
 | . 6 . | . 9 . | . . 8 |
 +-------+-------+-------+
 | . . 1 | 6 5 . | 2 . . |
 | 6 8 . | . . . | . 7 5 |
 | . . 9 | . 8 7 | 1 . . |
 +-------+-------+-------+
 | 7 . . | . 4 . | . 3 . |
 | . . 4 | . 6 . | . . 1 |
 | 9 . . | . . 3 | . . . |
 +-------+-------+-------+
 
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 Play this puzzle online at the Daily Sudoku site
 
 Last edited by Earl on Sat Oct 13, 2007 2:25 pm; edited 1 time in total
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		| TKiel 
 
 
 Joined: 22 Feb 2006
 Posts: 292
 Location: Kalamazoo, MI
 
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				|  Posted: Sat Oct 13, 2007 12:55 pm    Post subject: |   |  
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				| Basics run out here: 
 
  	  | Code: |  	  | *-----------------------------------------------------------*
 | 12    5     3     | 8     12    46    | 469   49    7     |
 | 4     9     8     | 3     7     126   | 5     12    26    |
 | 12    6     7     | 145   9     1245  | 3     124   8     |
 |-------------------+-------------------+-------------------|
 | 3     7     1     | 6     5     49    | 2     8     49    |
 | 6     8     2     | 149   3     149   | 49    7     5     |
 | 5     4     9     | 2     8     7     | 1     6     3     |
 |-------------------+-------------------+-------------------|
 | 7     12    56    | 159   4     8     | 69    3     269   |
 | 8     3     4     | 59    6     259   | 7     259   1     |
 | 9     12    56    | 7     12    3     | 8     45    46    |
 *-----------------------------------------------------------*
 
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 Coloring on <4> solves it.
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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Sat Oct 13, 2007 2:23 pm    Post subject: Sat Oct 13 DB |   |  
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				| Looking at Tracy's grid I saw an x-y wing based at R7C7 which eliminates the <4> at R4C9 and opens the puzzle. 
 Earl
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		| klimke 
 
 
 Joined: 17 Aug 2007
 Posts: 5
 
 
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				|  Posted: Sat Oct 13, 2007 3:15 pm    Post subject: |   |  
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				| I also noted an XYZ wing pivoting at r7c9 eliminating the 6 in r9c9 |  | 
	
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		| Johan 
 
 
 Joined: 25 Jun 2007
 Posts: 206
 Location: Bornem  Belgium
 
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				|  Posted: Sat Oct 13, 2007 5:19 pm    Post subject: |   |  
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				| The same XYZ-wing that klimke noted was the final step for me. |  | 
	
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sat Oct 13, 2007 6:12 pm    Post subject: |   |  
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				| I used basically the same XY-Wing, except the one that was pivoted in r9c9, which is really the same as the one in r7c7. |  | 
	
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