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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Fri Aug 28, 2009 4:51 pm    Post subject: Free Press 28 August, 2009 |   |  
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				| I'm starting to dislike these. Keith 	  | Code: |  	  | Puzzle: FP082809 +-------+-------+-------+
 | 5 . . | . . . | . . . |
 | . . . | . . . | . 6 . |
 | . . 3 | . . 2 | 7 4 . |
 +-------+-------+-------+
 | 4 . 7 | . 2 . | 3 . 8 |
 | . . . | . . . | . . . |
 | 3 . 2 | . 9 . | . . 5 |
 +-------+-------+-------+
 | . . 1 | 9 . 8 | 2 . . |
 | . 8 . | . . . | . 9 . |
 | . . . | . . 4 | . . 1 |
 +-------+-------+-------+
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		| storm_norm 
 
 
 Joined: 18 Oct 2007
 Posts: 1741
 
 
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				|  Posted: Fri Aug 28, 2009 6:49 pm    Post subject: |   |  
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				| after basics this one doesn't give up anything. no xy-wings, no x-wings, no xyz-wings, no type 1-4 UR's
 but I did find a way out.
 
  	  | Code: |  	  | .---------------------.---------------------.---------------------. | 5      247   *69    | 347    347    69    | 1      8      23    |
 | 2789   247   *49    | 1347   13478  379   | 5      6      23    |
 |-68     1      3     | 56     58     2     | 7      4      9     |
 :---------------------+---------------------+---------------------:
 | 4      9      7     | 56     2      56    | 3      1      8     |
 | 1      5      8     | 347    347    37    | 9      2      6     |
 | 3      6      2     | 8      9      1     | 4      7      5     |
 :---------------------+---------------------+---------------------:
 |*67     347    1     | 9      567    8     | 2      35    *47    |
 | 27     8     *45    | 1237   1357   357   | 6      9     *47    |
 | 2679   237    569   | 27     567    4     | 8      35     1     |
 '---------------------'---------------------'---------------------'
 | 
 (6=9)r1c3 - (9=4)r2c3 - (4)r8c3 = (4)r8c9 - (4=7)r7c9 - (7=6)r7c1; r3c1 <> 6
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		| arkietech 
 
 
 Joined: 31 Jul 2008
 Posts: 1834
 Location: Northwest Arkansas USA
 
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				|  Posted: Fri Aug 28, 2009 8:36 pm    Post subject: |   |  
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				|  	  | storm_norm wrote: |  	  | (6=9)r1c3 - (9=4)r2c3 - (4)r8c3 = (4)r8c9 - (4=7)r7c9 - (7=6)r7c1; r3c1 <> 6
 | 
 Beautiful
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		| daj95376 
 
 
 Joined: 23 Aug 2008
 Posts: 3854
 
 
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				|  Posted: Fri Aug 28, 2009 8:48 pm    Post subject: |   |  
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				| Well, there's always the Atypical Extension of Non-Productive Skyscraper. 
 
  	  | Code: |  	  | after basics: 
 non-productive Skyscraper for <6> in (*) cells
 strong link on <5> intersects one end of Skyscraper and sees the other
 
 (5)r3c5 = (5-6)r3c4 = r3c1 - r7c1 = (6  )r7c5 => [r7c5]<>5
 (5)r7c5 - (5)r3c5 = (5-6)r3c4 = r3c1 - r7c1 = (6-5)r7c5
 +-----------------------------------------------------------------------+
 |  5      247    69     |  347    347    69     |  1      8      23     |
 |  2789   247    49     |  1347   13478  379    |  5      6      23     |
 | *68     1      3      | *56    @58     2      |  7      4      9      |
 |-----------------------+-----------------------+-----------------------|
 |  4      9      7      |  56     2      56     |  3      1      8      |
 |  1      5      8      |  347    347    37     |  9      2      6      |
 |  3      6      2      |  8      9      1      |  4      7      5      |
 |-----------------------+-----------------------+-----------------------|
 | *67     347    1      |  9     *67-5   8      |  2      35     47     |
 |  27     8      45     |  1237   1357   357    |  6      9      47     |
 |  2679   237    569    |  27     567    4      |  8      35     1      |
 +-----------------------------------------------------------------------+
 # 64 eliminations remain
 
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  	  | Keith in original thread wrote: |  	  | I think this is pretty cool. How useful it is, we shall see. 
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 Does it qualify as useful?
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Fri Aug 28, 2009 9:16 pm    Post subject: |   |  
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				| Well, 
 There's also this:
  	  | Code: |  	  | +-------------------+-------------------+-------------------+ | 5     247   69    | 347   347   69    | 1     8     23    |
 | 2789  247   49    | 1347  13478 379   | 5     6     23    |
 | 68f   1     3     | 56    58e   2     | 7     4     9     |
 +-------------------+-------------------+-------------------+
 | 4     9     7     | 56    2     56    | 3     1     8     |
 | 1     5     8     | 347   347   37    | 9     2     6     |
 | 3     6     2     | 8     9     1     | 4     7     5     |
 +-------------------+-------------------+-------------------+
 | 67g   347b  1     | 9     567d  8     | 2     35c   47a   |
 | 27    8     45    | 1237  1357  357   | 6     9     47    |
 | 2679  237   569   | 27    567   4     | 8     35    1     |
 +-------------------+-------------------+-------------------+
 | 
 a <7> implies g <7>, so a <>7.
 
 I think this is kind of ugly (it is the same length as Norm's chain), but beauty is in the eye of the beholder!
 
 (There are shorter chains that make eliminations, but they are not one-steppers.)
 
 Keith
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		| daj95376 
 
 
 Joined: 23 Aug 2008
 Posts: 3854
 
 
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				|  Posted: Fri Aug 28, 2009 9:30 pm    Post subject: |   |  
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				|  	  | keith wrote: |  	  | (There are shorter chains that make eliminations, but they are not one-steppers.) 
 | 
 My chain is five cells and a one-stepper.
 
 
  	  | Code: |  	  | (5)r3c5 = (5-6)r3c4 = r3c1 - r7c1 = (6)r7c5 => [r7c5]<>5 
 | 
 Even the discontinuous loop form is only five (distinct) cells.
 
 
  	  | Code: |  	  | (5)r7c5 - (5)r3c5 = (5-6)r3c4 = r3c1 - r7c1 = (6-5)r7c5 
 | 
 There's also a 5-cell discontinuous loop in [band 3] that's a one-stepper.
 
 
  	  | Code: |  	  | (6-5)a = (5-4)b = (4)c - (4=7)d - (7=6)e - (6)a |-----------------------+-----------------------+-----------------------|
 | e67    c347    1      |  9      567    8      |  2      35    d47     |
 |  27     8     b45     |  1237   1357   357    |  6      9      47     |
 |  2679   237   a59-6   |  27     567    4      |  8      35     1      |
 +-----------------------------------------------------------------------+
 
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		| strmckr 
 
 
 Joined: 18 Aug 2009
 Posts: 66
 
 
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				|  Posted: Fri Aug 28, 2009 10:00 pm    Post subject: |   |  
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				| after basic this reduces it to singles. (4 cells) 
 WXYZ-WING: A=r7c29 {347}, B=r8c1,r9c2 {237}, X=3, Z=7 => r7c1<>7
 
 
  	  | Code: |  	  | .----------------.------------------.-----------. | 5     247  69  | 347   347    69  | 1  8   23 |
 | 2789  247  49  | 1347  13478  379 | 5  6   23 |
 | 68    1    3   | 56    58     2   | 7  4   9  |
 :----------------+------------------+-----------:
 | 4     9    7   | 56    2      56  | 3  1   8  |
 | 1     5    8   | 347   347    37  | 9  2   6  |
 | 3     6    2   | 8     9      1   | 4  7   5  |
 :----------------+------------------+-----------:
 | 6-7   347@ 1   | 9     567    8   | 2  35  47@|
 | 27@   8    45  | 1237  1357   357 | 6  9   47 |
 | 2679  237@ 569 | 27    567    4   | 8  35  1  |
 '----------------'------------------'-----------'
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		| arkietech 
 
 
 Joined: 31 Jul 2008
 Posts: 1834
 Location: Northwest Arkansas USA
 
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				|  Posted: Fri Aug 28, 2009 10:04 pm    Post subject: |   |  
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				|  	  | daj95376 wrote: |  	  | Well, there's always the Atypical Extension of Non-Productive Skyscraper. 
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 Cool and useful!
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sat Aug 29, 2009 5:02 am    Post subject: |   |  
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				| I looked at the potential DP of 35-37-57 in band 3. The first DP killer I looked at, the 4 in r7c2, was invalid and that's all that was needed. |  | 
	
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		| wapati 
 
 
 Joined: 10 Jun 2008
 Posts: 472
 Location: Brampton, Ontario, Canada.
 
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				|  Posted: Tue Sep 01, 2009 7:47 pm    Post subject: |   |  
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				|  	  | Marty R. wrote: |  	  | I looked at the potential DP of 35-37-57 in band 3. The first DP killer I looked at, the 4 in r7c2, was invalid and that's all that was needed. | 
 
 Marty,  column 5 r79 must have  a  six.
 If you have a deadly pattern it might be using 3567.
 
 I still don't understand what you mean about the 4 in r7c2.
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Tue Sep 01, 2009 9:17 pm    Post subject: |   |  
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				|  	  | wapati wrote: |  	  |  	  | Marty R. wrote: |  	  | I looked at the potential DP of 35-37-57 in band 3. The first DP killer I looked at, the 4 in r7c2, was invalid and that's all that was needed. | 
 
 Marty,  column 5 r79 must have  a  six.
 If you have a deadly pattern it might be using 3567.
 
 I still don't understand what you mean about the 4 in r7c2.
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 What I meant was that the 4 in r7c2 was one of the possibilities that could kill the DP. When I determined what would happen if r7c2=4, it led to an invalidity, therefore, the 4 had to be removed and that was enough to finish the puzzle.
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		| wapati 
 
 
 Joined: 10 Jun 2008
 Posts: 472
 Location: Brampton, Ontario, Canada.
 
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				|  Posted: Wed Sep 02, 2009 12:20 am    Post subject: |   |  
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				| Well,  an ick from me. 
 ?You had the wrong DP and your solving was identical to a guess.
 ( I'll try the 4,  it is wrong, I have it! )
 
 Anyways,  it worked.
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