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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Fri Dec 19, 2008 9:52 pm    Post subject: Yesterday's BB sh |   |  
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				| Just a touch more than this site's Very Hard: 
  	  | Code: |  	  | Puzzle: BB121808sh +-------+-------+-------+
 | 1 . . | . 2 . | . . 4 |
 | . . 8 | 3 . 9 | 5 . . |
 | . 2 . | . . . | . 8 . |
 +-------+-------+-------+
 | . 9 . | . 8 . | . 1 . |
 | 8 . . | 6 . 7 | . . 9 |
 | . 5 . | . 3 . | . 7 . |
 +-------+-------+-------+
 | . 7 . | . . . | . 5 . |
 | . . 5 | 4 . 2 | 6 . . |
 | 2 . . | . 9 . | . . 7 |
 +-------+-------+-------+
 | 
 
 Keith
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		| storm_norm 
 
 
 Joined: 18 Oct 2007
 Posts: 1741
 
 
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				|  Posted: Fri Dec 19, 2008 10:14 pm    Post subject: |   |  
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Fri Dec 19, 2008 10:24 pm    Post subject: |   |  
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				| I did not see that!  There are at least three other "advanced" moves.  After "basics": Keith 	  | Code: |  	  | +----------------+----------------+----------------+ | 1    36   369  | 58   2    58   | 7    369  4    |
 | 7    46   8    | 3    14   9    | 5    26   12   |
 | 5    2    349  | 7    14   6    | 19   8    13   |
 +----------------+----------------+----------------+
 | 6    9    7    | 2    8    4    | 3    1    5    |
 | 8    13   13   | 6    5    7    | 24   24   9    |
 | 4    5    2    | 9    3    1    | 8    7    6    |
 +----------------+----------------+----------------+
 | 39   7    14   | 18   6    38   | 1249 5    1238 |
 | 39   18   5    | 4    7    2    | 6    39   18   |
 | 2    1468 146  | 158  9    358  | 14   34   7    |
 +----------------+----------------+----------------+
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		| daj95376 
 
 
 Joined: 23 Aug 2008
 Posts: 3854
 
 
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				|  Posted: Fri Dec 19, 2008 10:46 pm    Post subject: |   |  
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				| Besides XY-Chains, did you see this companion to Norm's solution? 
 
  	  | Quote: |  	  | W-Wing <14> in Band 3 => [r7c7],[r9c23]<>4 
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Fri Dec 19, 2008 11:11 pm    Post subject: |   |  
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				| Another one-stepper:  	  | Quote: |  	  | UR <58> r19c46. Pseudo-cell <13> from UR & r9c78 gives subset <134>; delete <14> in r9c23 
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 Ted
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Sat Dec 20, 2008 12:09 am    Post subject: |   |  
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				| The <14> W-wing with 3 eliminations is really cool. 
 Yes, I saw the UR elimination on pencil & paper.  Is it a one-stepper?
 
 The way I solved it (P&P), after the UR, was with a pseudo-cell to create an extended XY-wing.
  	  | Code: |  	  | +----------------+----------------+----------------+ | 1    36   369  | 58   2    58   | 7   36-9  4    |
 | 7    46   8    | 3    14   9    | 5    26   12   |
 | 5    2    349  | 7    14   6    | 19a  8    13   |
 +----------------+----------------+----------------+
 | 6    9    7    | 2    8    4    | 3    1    5    |
 | 8    13   13   | 6    5    7    | 24   24   9    |
 | 4    5    2    | 9    3    1    | 8    7    6    |
 +----------------+----------------+----------------+
 | 39   7    14   | 18   6    38   | 1249 5    1238 |
 | 39   18   5    | 4    7    2    | 6    39d  18   |
 | 2    1468 146  | 158  9    358  | 14b  34c  7    |
 +----------------+----------------+----------------+
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 There are so many bi-value cells, there must be something!  Look at R89C8, c and d;  <39> and <34> means that these two cells contain one of <49>.  So a b cd is an extended XY-wing that takes out <9> in R1C8, solving the puzzle.
 
 I have taken to looking for these before I look for the possible pairs and strong links that might make skyscrapers, W-wings, etc.
 
 Keith
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		| cgordon 
 
 
 Joined: 04 May 2007
 Posts: 769
 Location: ontario, canada
 
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				|  Posted: Sat Dec 20, 2008 1:54 pm    Post subject: |   |  
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				| I am of course a heavy user of w-wings (since I learnt about them this week).  After a Type 4 UR (58) there were w -wings on 14 and 18. (I think).
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