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		| Clement 
 
 
 Joined: 24 Apr 2006
 Posts: 1113
 Location: Dar es Salaam Tanzania
 
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				|  Posted: Tue Dec 18, 2012 10:17 pm    Post subject: Dec 19 VH |   |  
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				| W-Wing 28 in BOX 27 with SL 8 in col 5; r8c6<>2. 	  | Code: |  	  | +----------+-----------+----------+
 | 7  9  8  | 5  4  6   | 1   3  2 |
 | 24 1  6  | 27 78 3   | 5   48 9 |
 | 24 3  5  | 9  1  *28  | 48  6  7 |
 +----------+-----------+----------+
 | 5  6  9  | 8  3  1   | 7   2  4 |
 | 8  4  1  | 6  2  7   | 9   5  3 |
 | 3  7  2  | 4  9  5   | 6   1  8 |
 +----------+-----------+----------+
 | 9  5  34 | 23 6  248 | 248 7  1 |
 | 6  *28 47 | 1  78 -248 | 3   9  5 |
 | 1  28 37 | 37 5  9   | 248 48 6 |
 +----------+-----------+----------+
 
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Wed Dec 19, 2012 2:48 am    Post subject: |   |  
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				|  	  | Code: |  	  | +----------+-----------+----------+
 | 7  9  8  | 5  4  6   | 1   3  2 |
 | 24 1  6  | 27 78 3   | 5   48 9 |
 | 24 3  5  | 9  1  28  | 48  6  7 |
 +----------+-----------+----------+
 | 5  6  9  | 8  3  1   | 7   2  4 |
 | 8  4  1  | 6  2  7   | 9   5  3 |
 | 3  7  2  | 4  9  5   | 6   1  8 |
 +----------+-----------+----------+
 | 9  5  34 | 23 6  248 | 248 7  1 |
 | 6  28 47 | 1  78 248 | 3   9  5 |
 | 1  28 37 | 37 5  9   | 248 48 6 |
 +----------+-----------+----------+
 
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 Play this puzzle online at the Daily Sudoku site
 
 Using only the standard VH techniques, I needed three moves.
 
 X-Wing (8), r37
 X-Wing (4), c36
 XYZ-Wing (248, pivot r7c6
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		| kuskey 
 
 
 Joined: 10 Dec 2008
 Posts: 141
 Location: Pembroke, NH
 
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				|  Posted: Wed Dec 19, 2012 6:41 am    Post subject: Dec 19 VH |   |  
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				| Marty: If you examine the intersection of r9 with box 9 in your grid you see that r7c7<>4 thus negating the x-wing in 4. After taking the x-wing in 8 the solution is either  your mentioned XYZ-wing <248> or the BUG+1.
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		| roaa 
 
 
 Joined: 18 Apr 2009
 Posts: 112
 Location: Sweden
 
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				|  Posted: Wed Dec 19, 2012 7:36 am    Post subject: Dec 19 VH |   |  
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				| After the x-wing on 8, the xy-wing 234 pivoting in r7c4 solves the puzzle. |  | 
	
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Wed Dec 19, 2012 4:12 pm    Post subject: |   |  
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				| Thanks. I can't seem to shed the problem of missing some basics from time to time.  |  | 
	
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		| George Woods 
 
 
 Joined: 28 Mar 2006
 Posts: 304
 Location: Dorset UK
 
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				|  Posted: Wed Dec 19, 2012 9:20 pm    Post subject: yet another almost an xy wing is a single stepper |   |  
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				| assume that r8c6 <> 8 then XY 234 pivoted at r7c4 quickly leads to  r8c5=8, So r7c6 cannot be 8 and this solves it |  | 
	
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