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		keith
 
 
  Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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				 Posted: Fri Jul 16, 2010 1:37 pm    Post subject: Free Press Jul 16, 2010 | 
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				 	  | Code: | 	 		  
 
Puzzle: FP071610
 
+-------+-------+-------+
 
| . . 5 | . . . | 6 . . |
 
| . 1 . | . . . | 8 3 . |
 
| . . 9 | . 6 . | . . 1 |
 
+-------+-------+-------+
 
| . 5 4 | 6 . . | . . . |
 
| . . . | 8 . 9 | . . . |
 
| . . . | . . 3 | 4 2 . |
 
+-------+-------+-------+
 
| 1 . . | . 5 . | 3 . . |
 
| . 4 2 | . 3 . | . 7 5 |
 
| . . 7 | . . . | 2 . . |
 
+-------+-------+-------+
 
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Play this puzzle online at the Daily Sudoku site
 
 
Keith | 
			 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Fri Jul 16, 2010 5:02 pm    Post subject:  | 
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				Possibly inefficient, but effective.
 
 
 	  | Quote: | 	 		  W-Wing (89)
 
Coloring (9)
 
M-Wing (27)
 
XYZ-Wing (279)
 
XY-Chain, r9c4<>1 | 	 
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		peterj
 
 
  Joined: 26 Mar 2010 Posts: 974 Location: London, UK
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				 Posted: Fri Jul 16, 2010 6:58 pm    Post subject:  | 
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				Here's a one-stepper found looking for a gm-wing around the 1&4 SL in box2 ...
 
 
 	  | Quote: | 	 		  A gm-wing(14) with a pseudo-cell one end and extended at the other...
 
 
(1=5)r5c8-(5=4)r3c8 - r3c6=(4-1)r1c6=r1c4 - (1)r8c4=r8c7; r5c7<>1
 
 
..or just another AIC if you prefer. | 	  
 
 
[Edit. Sorry I made 3 errors in this AIC - now fixed. Thanks, mm]
  Last edited by peterj on Sat Jul 17, 2010 4:42 pm; edited 4 times in total | 
			 
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		daj95376
 
 
  Joined: 23 Aug 2008 Posts: 3854
 
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				 Posted: Fri Jul 16, 2010 9:44 pm    Post subject:  | 
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				 	  | Code: | 	 		   (27=8)r13c2 - (8=6)r6c2 - UR[(6)r5c2 = (3)r1c1)]<27>r15c12  =>  r1c1<>27
 
 +-----------------------------------------------------------------------+
 
 |  27+3   27     5      |  12379  8      1247   |  6      49     279    |
 
 |  4      1      6      |  279    29     5      |  8      3      279    |
 
 |  2378   27+8   9      |  237    6      247    |  57     45     1      |
 
 |-----------------------+-----------------------+-----------------------|
 
 |  789    5      4      |  6      12     12     |  79     89     3      |
 
 |  27     27+6   3      |  8      4      9      |  15     15     67     |
 
 |  89     68     1      |  5      7      3      |  4      2      689    |
 
 |-----------------------+-----------------------+-----------------------|
 
 |  1      9      8      |  27     5      27     |  3      6      4      |
 
 |  6      4      2      |  19     3      8      |  19     7      5      |
 
 |  5      3      7      |  4      19     6      |  2      189    89     |
 
 +-----------------------------------------------------------------------+
 
 # 53 eliminations remain
 
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... followed by Marty's solution sans the XY-Chain.
  Last edited by daj95376 on Fri Jul 16, 2010 9:54 pm; edited 1 time in total | 
			 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Fri Jul 16, 2010 9:53 pm    Post subject:  | 
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				 	  | Quote: | 	 		  | ... followed by Marty's solution sans the XY-Chain. | 	  
 
Which means I missed some basics.    | 
			 
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		daj95376
 
 
  Joined: 23 Aug 2008 Posts: 3854
 
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				 Posted: Fri Jul 16, 2010 10:01 pm    Post subject:  | 
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				 	  | Marty R. wrote: | 	 		  Which means I missed some basics.    | 	  
 
I was simply swapping one step for another, but at different places in the sequence. I did not mean to imply that you'd missed any basics.
 
 
Regards, Danny | 
			 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Fri Jul 16, 2010 11:06 pm    Post subject:  | 
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				That's OK, you can imply or say directly, I don't mind. I interpreted if someone used my solution less the final step, then I had to have missed some basics if was solvable with my steps except for the last one? Am I missing something (besides basics)?    | 
			 
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		daj95376
 
 
  Joined: 23 Aug 2008 Posts: 3854
 
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				 Posted: Sat Jul 17, 2010 1:58 am    Post subject:  | 
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				 	  | Marty R. wrote: | 	 		  That's OK, you can imply or say directly, I don't mind. I interpreted if someone used my solution less the final step, then I had to have missed some basics if was solvable with my steps except for the last one? Am I missing something (besides basics)?    | 	  
 
That's a bad assumption -- especially in this case because I was just providing an alternate step. Since our solutions (essentially) matched except for my first step and your last step, I chose to not list all of the duplicate steps. I'm sorry that decision caused you to feel that you'd missed something.
 
 
Here is my full solution -- mostly found by my solver. Originally, the first step was UR eliminations through strong links. I went to examine that region closer and noticed the implications of r6c2=<68>. That's when I came up with my replacement first step.
 
 
 	  | Code: | 	 		   after basics:
 
 +-----------------------------------------------------------------------+
 
 |  237    27     5      |  12379  8      1247   |  6      49     279    |
 
 |  4      1      6      |  279    29     5      |  8      3      279    |
 
 |  2378   278    9      |  237    6      247    |  57     45     1      |
 
 |-----------------------+-----------------------+-----------------------|
 
 |  789    5      4      |  6      12     12     |  79     89     3      |
 
 |  27     267    3      |  8      4      9      |  15     15     67     |
 
 |  89     68     1      |  5      7      3      |  4      2      689    |
 
 |-----------------------+-----------------------+-----------------------|
 
 |  1      9      8      |  27     5      27     |  3      6      4      |
 
 |  6      4      2      |  19     3      8      |  19     7      5      |
 
 |  5      3      7      |  4      19     6      |  2      189    89     |
 
 +-----------------------------------------------------------------------+
 
 # 53 eliminations remain
 
 
 (27=8)r13c2 - (8=6)r6c2 - UR[(6)r5c2 = (3)r1c1)]<27>r15c12  =>  r1c1<>27
 
 
 <79+2>  XYZ-Wing r2c4/r2c5+r7c4         <> 2    r1c4   (or XY-Wing later)
 
 
 W-Wing (8=9)r4c8 - r4c7 = r8c7  - (9=8)r9c9  =>  r6c9,r9c8<>8   -or-
 
 W-Wing (8=9)r4c8 - r1c8 = r12c9 - (9=8)r9c9  =>  r6c9,r9c8<>8
 
 
 c58r9   Skyscraper                      <> 9    r1c4,r2c9
 
 
 M-Wing Type 7B (7=2)r1c2 - r1c9 = (2-7)r2c9 = (7)r2c4  =>  r1c46<>7
 
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My first step made it unnecessary for an XY-Chain after the M-Wing.
 
 
Regards, Danny | 
			 
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		tlanglet
 
 
  Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
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				 Posted: Sat Jul 17, 2010 3:35 am    Post subject:  | 
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				A patterned one stepper is
 
 
 	  | Quote: | 	 		  | ANP(27=4)r37c6-(4=5)r38-(5=7)r3c7-(7=9)r4c7-(9=1)r8c7-r8c4=r9c5-(1=2)r4c5; r4c6<>2 | 	  
 
Ted | 
			 
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		tlanglet
 
 
  Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
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				 Posted: Sat Jul 17, 2010 3:42 am    Post subject:  | 
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				 	  | daj95376 wrote: | 	 		   	  | Code: | 	 		   (27=8)r13c2 - (8=6)r6c2 - UR[(6)r5c2 = (3)r1c1)]<27>r15c12  =>  r1c1<>27
 
 +-----------------------------------------------------------------------+
 
 |  27+3   27     5      |  12379  8      1247   |  6      49     279    |
 
 |  4      1      6      |  279    29     5      |  8      3      279    |
 
 |  2378   27+8   9      |  237    6      247    |  57     45     1      |
 
 |-----------------------+-----------------------+-----------------------|
 
 |  789    5      4      |  6      12     12     |  79     89     3      |
 
 |  27     27+6   3      |  8      4      9      |  15     15     67     |
 
 |  89     68     1      |  5      7      3      |  4      2      689    |
 
 |-----------------------+-----------------------+-----------------------|
 
 |  1      9      8      |  27     5      27     |  3      6      4      |
 
 |  6      4      2      |  19     3      8      |  19     7      5      |
 
 |  5      3      7      |  4      19     6      |  2      189    89     |
 
 +-----------------------------------------------------------------------+
 
 # 53 eliminations remain
 
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  | 	  
 
 
Danny, very nice use of the Type 6 UR27. I looked at it in isolation but no deletions.
 
 
Ted | 
			 
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		keith
 
 
  Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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				 Posted: Sat Jul 17, 2010 8:57 am    Post subject:  | 
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				After basics: 	  | Code: | 	 		  +-------------------+-------------------+-------------------+
 
| 237   27    5     | 12379 8     1247  | 6     49    279   | 
 
| 4     1     6     | 279   29    5     | 8     3     279   | 
 
| 2378  278   9     | 237   6     247   | 57    45    1     | 
 
+-------------------+-------------------+-------------------+
 
| 789   5     4     | 6     12    12    | 79    89    3     | 
 
| 27    267   3     | 8     4     9     | 15    15    67    | 
 
| 89    68    1     | 5     7     3     | 4     2     689   | 
 
+-------------------+-------------------+-------------------+
 
| 1     9     8     | 27    5     27    | 3     6     4     | 
 
| 6     4     2     | 19    3     8     | 19    7     5     | 
 
| 5     3     7     | 4     19    6     | 2     189   89    | 
 
+-------------------+-------------------+-------------------+ | 	  
 
Pseudocell 59 in B3C8 makes an XY-wing 57-9.  R4C8 <>9.
 
M-wing 2-7.  R1B2 <>7.
 
XY-wing -279.  R13C4 <>2.
 
SS 9 in C58.  R1C4, R2C9 <> 9.
 
M-wing -79 with transport.  R1C9<>7.
 
Pseudocell 89 in R6 makes an XY-wing -289.  R1C12 <>2.
 
 
For what it's worth.
 
 
Keith | 
			 
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