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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Sun Jul 26, 2009 4:11 pm    Post subject: Free Press 24 July, 2009 |   |  
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				| I have not yet looked at this one. Keith 	  | Code: |  	  | Puzzle: FP072409 +-------+-------+-------+
 | . . 2 | . . 4 | . . . |
 | 4 . . | . . 8 | 3 . 7 |
 | 3 . . | 1 7 9 | . . 2 |
 +-------+-------+-------+
 | . 9 . | . . . | . 2 . |
 | 6 . . | . . . | . . 1 |
 | . 8 . | . . . | . 4 . |
 +-------+-------+-------+
 | 1 . . | 8 5 6 | . . 4 |
 | 7 . 4 | 2 . . | . . 6 |
 | . . . | 4 . . | 2 . . |
 +-------+-------+-------+
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Mon Jul 27, 2009 12:57 am    Post subject: |   |  
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				| This proved to be very stubborn for me, so it's probably a one-stepper. 
 
  	  | Quote: |  	  | Remote pairs (56), X-Wing (5), XY-Chain, M-Wing (39) with pincer transport and BUG+3 | 
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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Mon Jul 27, 2009 1:39 am    Post subject: free press |   |  
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				| I got it down to three steps. 
 Solution:  x-wing (5); xy-chain eliminates 3's in R6C5, R8C5; 169 xy-wing eliminates 9 in R8C7 to solve the puzzle.
 
 
 Earl
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Mon Jul 27, 2009 2:32 am    Post subject: |   |  
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				| Marty, 
 My solution was similar to yours:  Remote pair, X-wing, extended XY-wing <356> and pincer coloring, XY-wing.
 
 Keith
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		| storm_norm 
 
 
 Joined: 18 Oct 2007
 Posts: 1741
 
 
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				|  Posted: Mon Jul 27, 2009 4:26 am    Post subject: |   |  
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				|  	  | Code: |  	  | .------------------.------------------.------------------. | 9     7     2    | 356   36    4    | 18    1568  58   |
 | 4     1    *56   |*56    2     8    | 3     9     7    |
 | 3    *56    8    | 1     7     9    | 4     56    2    |
 :------------------+------------------+------------------:
 | 5     9     17   |3-67    4   *13   |*68    2    *38   |
 | 6     4     3    | 9     8     2    | 5     7     1    |
 | 2     8     17   | 367   136   5    | 69    4     39   |
 :------------------+------------------+------------------:
 | 1     2     9    | 8     5     6    | 7     3     4    |
 | 7    *35    4    | 2     139  *13   | 189   158   6    |
 | 8     356   56   | 4     139   7    | 2     15    59   |
 '------------------'------------------'------------------'
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 (6=8)r4c7 - (8=3)r4c9 - (3=1)r4c6 - (1=3)r8c6 - (3=5)r8c2 - (5=6)r3c2 - (6)r2c3 = (6)r2c4; r4c4 <> 6
 
 Last edited by storm_norm on Mon Jul 27, 2009 4:50 pm; edited 2 times in total
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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Mon Jul 27, 2009 3:55 pm    Post subject: free press |   |  
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				| Norm, 
 How do you see those paths?  When you point them out I can follow, but spotting them in the first place is beyond me.
 
 Earl
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		| daj95376 
 
 
 Joined: 23 Aug 2008
 Posts: 3854
 
 
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				|  Posted: Mon Jul 27, 2009 6:03 pm    Post subject: |   |  
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				| Interesting. With little effort, this puzzle reduces to this BUG+5. However, showing that [r6c4]=6 is the only valid possibility is beyond me. Thus, I used a chain (found by my solver). 
 
  	  | Code: |  	  | (  1)r6c5 = (1-9)r8c5 = (9)r8c7 - (9=6)r6c7           => [r6c5]<>6   -or- (6-1)r6c5 = (1-9)r8c5 = (9)r8c7 - (9=6)r6c7 - (6)r6c5 => [r6c5]<>6
 +-----------------------------------------------------+
 |  9    7    2    |  35+6 36   4    |  1    68   58   |
 |  4    1    56   |  56   2    8    |  3    9    7    |
 |  3    56   8    |  1    7    9    |  4    56   2    |
 |-----------------+-----------------+-----------------|
 |  5    9    17   |  67+3 4    13   |  68   2    38   |
 |  6    4    3    |  9    8    2    |  5    7    1    |
 |  2    8    17   |  37+6 16+3 5    |  69   4    39   |
 |-----------------+-----------------+-----------------|
 |  1    2    9    |  8    5    6    |  7    3    4    |
 |  7    35   4    |  2    19+3 13   |  89   58   6    |
 |  8    36   56   |  4    39   7    |  2    1    59   |
 +-----------------------------------------------------+
 # 32 eliminations remain
 
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 Note: The first chain is logically acceptable, but the second chain dots all of the Is and crosses all of the Ts.
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Mon Jul 27, 2009 8:39 pm    Post subject: |   |  
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				|  	  | Code: |  	  | +-------------+-------------+-------------+ | 9   7   2   | 356 36e 4   | 1   68  58  |
 | 4   1   56c | 56d 2   8   | 3   9   7   |
 | 3   56b 8   | 1   7   9   | 4   56  2   |
 +-------------+-------------+-------------+
 | 5   9   17  | 367 4   13  | 68  2   38  |
 | 6   4   3   | 9   8   2   | 5   7   1   |
 | 2   8   17  |367 -136 5   | 69  4   39  |
 +-------------+-------------+-------------+
 | 1   2   9   | 8   5   6   | 7   3   4   |
 | 7   35a 4   | 2  1-39 13  | 89  58  6   |
 | 8   36f 56  | 4   39g 7   | 2   1   59  |
 +-------------+-------------+-------------+
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 The extended XY-wing abcde takes out <3> in R8C5.  Coloring a to f and g takes out <3> in R6C5.  Leaving an XY-wing <169> that solves R8C7 as <8>.
 
 Keith
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Tue Jul 28, 2009 2:07 pm    Post subject: |   |  
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				| I ended up with a two step solution: a extended xy-wing -356 with pivot 56 in r2c4 and one pincer in r1c5. An extended pincer(E) plus a pincer transport(T) delete 3 in r68c5 (which I strongly suspect is the chain used by Earl),
 
  	  | Code: |  	  | *-----------------------------------------------------------*
 | 9     7     2     | 356   36    4     | 18    1568  58    |
 | 4     1    E56    |P56    2     8     | 3     9     7     |
 | 3    E56    8     | 1     7     9     | 4     56    2     |
 |-------------------+-------------------+-------------------|
 | 5     9     17    | 367   4     13    | 68    2     38    |
 | 6     4     3     | 9     8     2     | 5     7     1     |
 | 2     8     17    | 367  1-36   5     | 69    4     39    |
 |-------------------+-------------------+-------------------|
 | 1     2     9     | 8     5     6     | 7     3     4     |
 | 7    E35    4     | 2    1-39   13    | 189   158   6     |
 | 8    T356   56    | 4    T139   7     | 2     15    59    |
 *-----------------------------------------------------------*
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 The previous moves opens a xy-wing 13-6 with pivot 13 in r4c6 and a pseudocell in r4c79.
 
 Ted
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