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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 :
 
 	  | 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  |
 
+-------------------+--------------+---------------+ | 	  In order to avoid the unresolvable loop (28)r4c13,r7c38,r9c18 : [6r4c13=5r9c1-(5=6)r8c1]-(6=8)r6c1; stte
 
 
Analysis of the puzzle from B6 gives :
 
 	  | 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 |
 
+---------------+-----------------+--------------+
 
 | 	  ALS-Wing[5r8c7=7r8c4-7r9c5=(7-5)r4c5=5r5c5]-(5=3)r5c7; stte of a unique solution | 
			 
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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
 
 	  | 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 |
 
+----------------+------------------+------------+
 
 | 	  Wing{4C5, 7C5, (78)r4c4} -> -8r6c5; stte | 
			 
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