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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Mon Feb 15, 2016 8:00 pm    Post subject: Free Press Thu 17 Dec 2015 |   |  
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				| The Free Press puzzles have gotten much more interesting.  Now, the Thu and Sun puzzles often need advanced moves, while the Fri one needs chains. 
  	  | Code: |  	  | +-------+-------+-------+ | . . 7 | . . . | 9 5 . |
 | . . . | . 1 . | . . . |
 | . . . | . . 7 | . 3 2 |
 +-------+-------+-------+
 | . 3 . | . . . | 4 1 . |
 | 7 . . | 6 . 2 | . . 8 |
 | . 9 5 | . . . | . 7 . |
 +-------+-------+-------+
 | 3 4 . | 9 . 5 | . . . |
 | . . . | . 2 8 | . . . |
 | . . 9 | . . . | 6 . . |
 +-------+-------+-------+
 | 
 
 Keith
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Mon Feb 15, 2016 9:45 pm    Post subject: |   |  
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				|  	  | Code: |  	  | +-------------+------------+----------+
 | 1   28  7   | 238 38  6  | 9  5  4  |
 | 9   25  3   | 25  1   4  | 8  6  7  |
 | 4   568 68  | 58  9   7  | 1  3  2  |
 +-------------+------------+----------+
 | 268 3   268 | 78  578 9  | 4  1  56 |
 | 7   1   4   | 6   35  2  | 35 9  8  |
 | 68  9   5   | 14  348 13 | 2  7  36 |
 +-------------+------------+----------+
 | 3   4   28  | 9   6   5  | 7  28 1  |
 | 56  67  1   | 37  2   8  | 35 4  9  |
 | 258 78  9   | 14  347 13 | 6  28 35 |
 +-------------+------------+----------+
 
 | 
 Play this puzzle online at the Daily Sudoku site
 This one's a Thursday, so presumably an advanced move could do it, but I didn't find it, so here's my chain.
 
 (7=6)r8c2-(6=5)r8c1-(5=3)r8c7-r5c7=r5c5-(3=1487)b5p7891=> -7r8c4
 
 P.S. A note on the notation of the last term, which I haven't yet seen on this forum. b=box, p=point or position, referring to the position of the cells in the box, 1-9 going left to right and down. This is an excellent shortcut for an ALS within a box.
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		| JC Van Hay 
 
 
 Joined: 13 Jun 2010
 Posts: 494
 Location: Charleroi, Belgium
 
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				|  Posted: Mon Feb 15, 2016 9:59 pm    Post subject: |   |  
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				| Just for the fun : 
 In order to avoid the unresolvable loop (28)r4c13,r7c38,r9c18 : [6r4c13=5r9c1-(5=6)r8c1]-(6=8)r6c1; stte 	  | Code: |  	  | +-------------------+--------------+---------------+ | 1      28   7     | 238  38   6  | 9   5     4   |
 | 9      25   3     | 25   1    4  | 8   6     7   |
 | 4      568  68    | 58   9    7  | 1   3     2   |
 +-------------------+--------------+---------------+
 | (268)  3    (268) | 78   578  9  | 4   1     56  |
 | 7      1    4     | 6    35   2  | 35  9     8   |
 | 8(-6)  9    5     | 14   348  13 | 2   7     36  |
 +-------------------+--------------+---------------+
 | 3      4    (28)  | 9    6    5  | 7   (28)  1   |
 | (56)   67   1     | 37   2    8  | 35  4     9   |
 | (258)  78   9     | 14   347  13 | 6   (28)  35  |
 +-------------------+--------------+---------------+
 | 
 
 Analysis of the puzzle from B6 gives :
 
 ALS-Wing[5r8c7=7r8c4-7r9c5=(7-5)r4c5=5r5c5]-(5=3)r5c7; stte of a unique solution 	  | Code: |  	  | +---------------+-----------------+--------------+ | 1    28   7   | 238   38     6  | 9     5   4  |
 | 9    25   3   | 25    1      4  | 8     6   7  |
 | 4    568  68  | 58    9      7  | 1     3   2  |
 +---------------+-----------------+--------------+
 | 268  3    268 | 78    8(57)  9  | 4     1   56 |
 | 7    1    4   | 6     3(5)   2  | 3-5   9   8  |
 | 68   9    5   | 14    348    13 | 2     7   36 |
 +---------------+-----------------+--------------+
 | 3    4    28  | 9     6      5  | 7     28  1  |
 | 56   67   1   | (37)  2      8  | (35)  4   9  |
 | 258  78   9   | 14    34(7)  13 | 6     28  35 |
 +---------------+-----------------+--------------+
 
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Tue Feb 16, 2016 1:39 pm    Post subject: |   |  
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				| JC, 
 There's a remote pair (35) not needed.
 
 There's an X-wing on 3  in C69 that reveals an XY-wing 4-78 that solves it.
 
 Keith
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		| dongrave 
 
 
 Joined: 06 Mar 2014
 Posts: 572
 
 
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				|  Posted: Tue Feb 16, 2016 2:25 pm    Post subject: |   |  
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				| Darn x wings!  There ought be a law against them. |  | 
	
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Tue Feb 16, 2016 2:59 pm    Post subject: |   |  
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				|  	  | dongrave wrote: |  	  | Darn x wings!  There ought be a law against them. | 
 At least we should admit they're a fish and not a wing.
 
 Keith
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		| JC Van Hay 
 
 
 Joined: 13 Jun 2010
 Posts: 494
 Location: Charleroi, Belgium
 
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				|  Posted: Tue Feb 16, 2016 3:31 pm    Post subject: |   |  
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				| Another (and simpler) optimized solution suggested by the analysis of the puzzle from B6 : 
 23 singles
 Pointing{5B2} -> -5r4c4
 HP{1C4, 4C4} -> -(378)r69c4
 
 Wing{4C5, 7C5, (78)r4c4} -> -8r6c5; stte 	  | Code: |  	  | +----------------+------------------+------------+ | 1    28    7   | 238   38      6  | 9   5   4  |
 | 9    25    3   | 25    1       4  | 8   6   7  |
 | 4    568   68  | 58    9       7  | 1   3   2  |
 +----------------+------------------+------------+
 | 268  3     268 | (78)  58(7)   9  | 4   1   56 |
 | 7    1     4   | 6     35      2  | 35  9   8  |
 | 68   9     5   | 14    3-8(4)  13 | 2   7   36 |
 +----------------+------------------+------------+
 | 3    4     28  | 9     6       5  | 7   28  1  |
 | 56   567   1   | 37    2       8  | 35  4   9  |
 | 258  2578  9   | 14    3(47)   13 | 6   28  35 |
 +----------------+------------------+------------+
 
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