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		daj95376
 
 
  Joined: 23 Aug 2008 Posts: 3854
 
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				 Posted: Sat May 21, 2011 11:15 pm    Post subject: Puzzle 11/05/21: ~ XY | 
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				 	  | Hint wrote: | 	 		  | search for URs first among advanced techniques!   . | 	  
 
 
 	  | Code: | 	 		   +-----------------------+
 
 | 5 . . | 4 . . | . . 1 |
 
 | . 2 . | 6 1 . | . . 7 |
 
 | . . 1 | 2 5 . | 6 . . |
 
 |-------+-------+-------|
 
 | 8 4 3 | . . . | 5 1 . |
 
 | . 1 7 | . 2 4 | 3 . . |
 
 | . . . | . 3 . | 4 . 6 |
 
 |-------+-------+-------|
 
 | . . 9 | 1 8 5 | 7 . . |
 
 | . . . | 9 . . | . . . |
 
 | 7 8 . | . . 2 | . . 5 |
 
 +-----------------------+
 
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Play this puzzle online at the Daily Sudoku site | 
			 
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		peterj
 
 
  Joined: 26 Mar 2010 Posts: 974 Location: London, UK
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				 Posted: Sun May 22, 2011 10:58 am    Post subject:  | 
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				Two steps...
 
 	  | Quote: | 	 		  xy-wing(36-4)r7c2 ; r7c1<>4
 
general remotepair(23) r7c1, r1c8 ; r7c8<>23 | 	  
 
I looked at the hint...
 
 	  | Quote: | 	 		  But I didn't spot anything much - except after the xy-wing there was an overlapping UR(34), UR(38) which made r8c9<>8.
 
I often miss these UR moves... | 	 
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		daj95376
 
 
  Joined: 23 Aug 2008 Posts: 3854
 
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				 Posted: Sun May 22, 2011 5:02 pm    Post subject:  | 
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				Peter's general Remote Pair definitely works better than my hint:
 
 
 	  | Code: | 	 		   XY-Wing <36+4>      =>       r7c1<>4   (step: 1)
 
 
 <34> UR Type 6      =>  r3c8,r7c9<>3   (step: 2)  grid below
 
 
 2-String Kite r1c1  =>       r7c8<>3   (step: 3)
 
 
 BUG+1               =>       r8c8= 2   (step: 4)
 
 +---------------------------------------------------------------+
 
 |  5     39    6     |  4     7     89    |  28    23     1     |
 
 |  4     2     8     |  6     1     3     |  9     5      7     |
 
 |  39    7     1     |  2     5     89    |  6    *34    *34+8  |
 
 |--------------------+--------------------+---------------------|
 
 |  8     4     3     |  7     9     6     |  5     1      2     |
 
 |  6     1     7     |  5     2     4     |  3     8      9     |
 
 |  29    59    25    |  8     3     1     |  4     7      6     |
 
 |--------------------+--------------------+---------------------|
 
 |  23    36    9     |  1     8     5     |  7    *34+26 *34    |
 
 |  1     356   25    |  9     4     7     |  28    236    38    |
 
 |  7     8     4     |  3     6     2     |  1     9      5     |
 
 +---------------------------------------------------------------+
 
 # 25 eliminations remain
 
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Nice catch Peter! | 
			 
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		peterj
 
 
  Joined: 26 Mar 2010 Posts: 974 Location: London, UK
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				 Posted: Mon May 23, 2011 2:44 pm    Post subject:  | 
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				Just for the record, the MUG I found after the xy-wing for a two-step was ...
 
  	  | Code: | 	 		  *------------------------------------------------------------*
 
 | 5     39    6     | 4     7     89    | 28    23     1     |
 
 | 4     2     8     | 6     1     3     | 9     5      7     |
 
 | 39    7     1     | 2     5     89    | 6    *34    *34+8  |
 
 |-------------------+-------------------+--------------------|
 
 | 8     4     3     | 7     9     6     | 5     1      2     |
 
 | 6     1     7     | 5     2     4     | 3     8      9     |
 
 | 29    59    25    | 8     3     1     | 4     7      6     |
 
 |-------------------+-------------------+--------------------|
 
 | 23   *36    9     | 1     8     5     | 7    *346+2 *34    |
 
 | 1    *36+5  25    | 9     4     7     | 28   *36+2   3-8   |
 
 | 7     8     4     | 3     6     2     | 1     9      5     |
 
 *------------------------------------------------------------* | 	  
 
I think the MUG is formed from a UR(34) and UR(36) overlapping at r7c8
 
 	  | Code: | 	 		  MUG(346) ; r8c9<>8
 
(5)r8c2 - (5=2)r8c3 - (2=8)r8c7
 
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(8)r3c9
 
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(2)r78c8 - (2=8)r8c7 | 	 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Tue May 24, 2011 4:59 am    Post subject:  | 
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				I took four steps.
 
 
XY-Wing (364)
 
Type 6 UR (34)
 
Skyscraper (3)
 
BUG+1 | 
			 
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