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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Sat Nov 01, 2008 11:51 am    Post subject: Nov 1 DB |   |  
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				| November begins with this DB which can be solved with an xy-chain eliminating the 7 in R1C9.  That's the only single-step solution I could find. 
 Earl
 
 
  	  | Code: |  	  | +-------+-------+-------+
 | 5 8 . | . . . | 9 4 . |
 | . . 4 | . 5 . | . 8 . |
 | . . 3 | 8 1 . | 5 . . |
 +-------+-------+-------+
 | . . 9 | . . 6 | . 7 . |
 | . 2 . | . . . | . 3 . |
 | . 7 . | 9 . . | 1 . . |
 +-------+-------+-------+
 | . . 6 | . 2 7 | 4 . . |
 | . 3 . | . 9 . | 7 . . |
 | . 4 7 | . . . | . 2 5 |
 +-------+-------+-------+
 
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 Play this puzzle online at the Daily Sudoku site
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Sat Nov 01, 2008 2:56 pm    Post subject: |   |  
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				| Keith 	  | Quote: |  	  | I had an X-wing and a couple of nice W-wings. | 
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		| cgordon 
 
 
 Joined: 04 May 2007
 Posts: 769
 Location: ontario, canada
 
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				|  Posted: Sat Nov 01, 2008 4:01 pm    Post subject: |   |  
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				| Not into chains or W's - but there are two plain old xy-wings for 248 and  238. |  | 
	
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sat Nov 01, 2008 4:43 pm    Post subject: |   |  
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				|  	  | Code: |  	  | +-----------+------------+-----------+
 | 5   8  12 | 267 67 3   | 9  4 127  |
 | 127 6  4  | 27  5  9   | 23 8 1237 |
 | 27  9  3  | 8   1  4   | 5  6 27   |
 +-----------+------------+-----------+
 | 3   15 9  | 15  4  6   | 28 7 28   |
 | 4   2  15 | 17  78 158 | 6  3 9    |
 | 6   7  8  | 9   3  2   | 1  5 4    |
 +-----------+------------+-----------+
 | 18  15 6  | 35  2  7   | 4  9 38   |
 | 28  3  25 | 4   9  58  | 7  1 6    |
 | 9   4  7  | 136 68 18  | 38 2 5    |
 +-----------+------------+-----------+
 
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 Play this puzzle online at the Daily Sudoku site
 
 The 27 W-Wing in boxes 23 is enough.
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Sat Nov 01, 2008 5:16 pm    Post subject: |   |  
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				| I don't see them. 	  | cgordon wrote: |  	  | Not into chains or W's - but there are two plain old xy-wings for 248 and  238. | 
 
 After basics:
 
  	  | Code: |  	  | +----------------+----------------+----------------+ | 5    8    12$  | 267  67   3    | 9    4   1-27% |
 |1-27% 6    4    | 27   5    9    | 23$  8    1237 |
 | 27&  9    3    | 8    1    4    | 5    6    27@  |
 +----------------+----------------+----------------+
 | 3    15   9    | 15   4    6    | 28   7    28@  |
 | 4    2    15   |1-57  78   158  | 6    3    9    |
 | 6    7    8    | 9    3    2    | 1    5    4    |
 +----------------+----------------+----------------+
 | 18#  15   6    | 35   2    7    | 4    9    38#  |
 | 28@  3    25   | 4    9    58   | 7    1    6    |
 | 9    4    7    | 136  68   18   | 38   2    5    |
 +----------------+----------------+----------------+
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 X-wing in R47 takes out <5> in R5C4. (not needed?)
 
 The cells @ are a W-wing, eliminating <2>.  The pincers can be transported by coloring on <2> to the cells $.  They take out <2> in the cells marked %.  These cells % are now a W-wing eliminating <1> !
 
   
 Solving R1C3 as <2>, and solving the puzzle.
 
 Keith
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		| cgordon 
 
 
 Joined: 04 May 2007
 Posts: 769
 Location: ontario, canada
 
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				|  Posted: Sat Nov 01, 2008 6:10 pm    Post subject: |   |  
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				| 
 Keith:  I must be basics-challenged cos I got nowhere near your grid. After basics I still have unsolved cells at R1C6, R6C569.  So my first xy-wing for 248 can be found at pivot R4C7 and wings R6C9, R4C5.  The other xy wing comes later.
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