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		| yeoks 
 
 
 Joined: 16 May 2010
 Posts: 33
 
 
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				|  Posted: Sun May 16, 2010 6:38 am    Post subject: May 16 VH |   |  
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				| XY-Wing 16 15 56 takes out 6 in r7c6 followed by another 15 25 12 removing 1 from r3c3
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		| peterj 
 
 
 Joined: 26 Mar 2010
 Posts: 974
 Location: London, UK
 
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				|  Posted: Sun May 16, 2010 10:39 am    Post subject: |   |  
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				| This one didn't seem to want to solve any other way than the 2 xy-wings for me! 
 Though I did waste 10 minutes of my life on a long xy-chain starting (5=1)r1c1 and ending (6=5)r7c7 eliminating 5 from r7c1. This left only the first of the xy-wings.
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		| Kdelle 
 
 
 Joined: 20 Mar 2008
 Posts: 59
 Location: Hudson, NH
 
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				|  Posted: Sun May 16, 2010 12:47 pm    Post subject: |   |  
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				| I needed two wings also, but I used the 258 XY wing as my second. 
 Kathy
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		| Clement 
 
 
 Joined: 24 Apr 2006
 Posts: 1113
 Location: Dar es Salaam Tanzania
 
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				|  Posted: Sun May 16, 2010 3:02 pm    Post subject: |   |  
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				| yeoks, I cannot see the XY-Wing 16 15 56. Can you indicate the cells where the pivot and pincers are which take out 6 in r7c6.
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sun May 16, 2010 3:35 pm    Post subject: |   |  
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				|  	  | Clement wrote: |  	  | yeoks, I cannot see the XY-Wing 16 15 56. Can you indicate the cells where the pivot and pincers are which take out 6 in r7c6.
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 Pivot in r2c7.
 
 
 
  	  | Code: |  	  | +-------------+-------------+--------------+
 | 15  36  9   | 125 26  8   | 7  345  1345 |
 | 8   36  4   | 9   7   16  | 15 35   2    |
 | 7   2   15  | 15  3   4   | 8  6    9    |
 +-------------+-------------+--------------+
 | 24  1   28  | 6   9   5   | 3  248  7    |
 | 249 89  6   | 3   1   7   | 45 2458 458  |
 | 3   5   7   | 8   4   2   | 16 9    16   |
 +-------------+-------------+--------------+
 | 259 4   3   | 7   268 69  | 56 1    568  |
 | 6   78  12  | 12  5   3   | 9  478  48   |
 | 159 789 158 | 4   68  169 | 2  3578 3568 |
 +-------------+-------------+--------------+
 
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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: Sun May 16, 2010 5:11 pm    Post subject: |   |  
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				| The XY-wing is in R24C67.  The rectangular ones are tough to see! 	  | Marty R. wrote: |  	  |  	  | Clement wrote: |  	  | yeoks, I cannot see the XY-Wing 16 15 56. Can you indicate the cells where the pivot and pincers are which take out 6 in r7c6.
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 Pivot in r2c7.
 
 
 
  	  | Code: |  	  | +-------------+-------------+--------------+
 | 15  36  9   | 125 26  8   | 7  345  1345 |
 | 8   36  4   | 9   7   16  | 15 35   2    |
 | 7   2   15  | 15  3   4   | 8  6    9    |
 +-------------+-------------+--------------+
 | 24  1   28  | 6   9   5   | 3  248  7    |
 | 249 89  6   | 3   1   7   | 45 2458 458  |
 | 3   5   7   | 8   4   2   | 16 9    16   |
 +-------------+-------------+--------------+
 | 259 4   3   | 7   268 69  | 56 1    568  |
 | 6   78  12  | 12  5   3   | 9  478  48   |
 | 159 789 158 | 4   68  169 | 2  3578 3568 |
 +-------------+-------------+--------------+
 
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 Play this puzzle online at the Daily Sudoku site
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 (Maybe it needs a different name
  ) 
 Marty,
 
 In this grid you can solve R5C6 as a single, and then R4C1.
 
 Keith
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sun May 16, 2010 5:17 pm    Post subject: |   |  
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				| Keith, sorry, I don't understand either of your two statements.  |  | 
	
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		| George Woods 
 
 
 Joined: 28 Mar 2006
 Posts: 304
 Location: Dorset UK
 
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				|  Posted: Sun May 16, 2010 5:32 pm    Post subject: xy wing |   |  
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				|  	  | Marty R. wrote: |  	  | Keith, sorry, I don't understand either of your two statements.  | 
 
 if you look in row 2 you will see a  16 and a 15 so if you are to find an x wing one of thes cells will "see" a 56 vertically
 
 
 Hope this helps
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		| peterj 
 
 
 Joined: 26 Mar 2010
 Posts: 974
 Location: London, UK
 
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				|  Posted: Sun May 16, 2010 6:01 pm    Post subject: |   |  
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				| By rectangular I guess Keith means the 'three block' type of xy-wing. 
 They are definitely much harder to see (for me) especially if they are a long way apart - I often stumble on them when looking for xy-chains (my standard move after colouring when I am lacking inspiration!)
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Sun May 16, 2010 6:05 pm    Post subject: |   |  
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				| [quote="keith"]  	  | Marty R. wrote: |  	  |  	  | Clement wrote: |  	  | yeoks, I cannot see the XY-Wing 16 15 56. Can you indicate the cells where the pivot and pincers are which take out 6 in r7c6.
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 The XY-wing is in R24C67.  The rectangular ones are tough to see!
 
 (Maybe it needs a different name
  ) 
 Marty,
 
 In this grid you can solve R5C6 as a single, and then R4C1.
 
 Keith
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 OOPS!  Should be:
 The XY-wing is in R27C67.
 
 If the three cells of the XY-wing (one pivot plus two pincers) lie on the corners of a rectangle, there can be an elimination in only one cell.  I find these hard to spot.
 
 The comment about the name is a jab at those who would name every variant of two strong links.
 
 OOPS 2!  Should be:
 In this grid you can solve R5C7as a single, and then R4C1.  They are both 4.
 
 
 Keith
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		| Wendy W 
 
 
 Joined: 04 Feb 2008
 Posts: 144
 
 
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				|  Posted: Sun May 16, 2010 7:37 pm    Post subject: |   |  
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				| Two xy-wings for me, just like yeoks: 156 and 125. There was also an xyz-wing 568 but it wasn't necessary. |  | 
	
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Sun May 16, 2010 9:45 pm    Post subject: |   |  
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				| There is also an unnecessary X-wing. 	  | Wendy W wrote: |  	  | There was also an xyz-wing 568 but it wasn't necessary. | 
   
 Keith
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		| Wendy W 
 
 
 Joined: 04 Feb 2008
 Posts: 144
 
 
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				|  Posted: Mon May 17, 2010 3:04 pm    Post subject: |   |  
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				| Geez, Keith, you had to go and point that out, didn't you!  My problem is a lack of patience: Once I find a wing of any sort, I just don't feel like going back and doing the meticulous basics all over again -- I just want to find more! |  | 
	
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