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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. | 	  
 
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 |
 
+-------------+-------------+--------------+
 
 | 	  
 
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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				 	  | 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. | 	  
 
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 |
 
+-------------+-------------+--------------+
 
 | 	  
 
Play this puzzle online at the Daily Sudoku site | 	  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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		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. | 	  
 
 
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 | 	  
 
 
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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				 	  | Wendy W wrote: | 	 		  | There was also an xyz-wing 568 but it wasn't necessary. | 	  There is also an unnecessary X-wing.     
 
 
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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