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		| hughwill 
 
 
 Joined: 05 Apr 2010
 Posts: 424
 Location: Birmingham UK
 
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				|  Posted: Thu Jun 02, 2016 9:44 am    Post subject: Jun 2 VH |   |  
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				| After basics:  	  | Code: |  	  | +------------+------------+---------+
 | 68  39  5  | 2   389  4 | 69 7 1  |
 | 178 2   89 | 789 1389 6 | 49 5 34 |
 | 167 139 4  | 79  139  5 | 2  8 36 |
 +------------+------------+---------+
 | 5   49  69 | 3   7    1 | 46 2 8  |
 | 168 14  68 | 5   2    9 | 7  3 46 |
 | 3   7   2  | 6   4    8 | 5  1 9  |
 +------------+------------+---------+
 | 2   6   1  | 89  89   7 | 3  4 5  |
 | 4   5   3  | 1   6    2 | 8  9 7  |
 | 9   8   7  | 4   5    3 | 1  6 2  |
 +------------+------------+---------+
 
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 Play this puzzle online at the Daily Sudoku site
 
 This one's quite neat compared to the frequent bland fare:
 There are two XY-Wings that end in the same elimination-
 69-3 pivot at r3c9 and 46-9 on r1c7,pivot r4c7,r4c2 both
 lead to r1c2=3. Unfortunately this doesn't lead to a stte conclusion.
 But what's this?
 is a one-stepper. 	  | Quote: |  	  | the other 46-9 on r2c7,pivot (again!) r4c7 r4c2 r2c3=8 | 
 
 Two XYs with the same numbers and same pivot- one does it and
 the other doesn't. Classic.
 
 Hugh
   (select the white space under Quote to see the solution)
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Thu Jun 02, 2016 12:00 pm    Post subject: Re: Jun 2 VH |   |  
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				|  	  | hughwill wrote: |  	  | After basics:  	  | Code: |  	  | +------------+------------+---------+
 | 68  39  5  | 2   389  4 | 69 7 1  |
 | 178 2   89 | 789 1389 6 | 49 5 34 |
 | 167 139 4  | 79  139  5 | 2  8 36 |
 +------------+------------+---------+
 | 5   49  69 | 3   7    1 | 46 2 8  |
 | 168 14  68 | 5   2    9 | 7  3 46 |
 | 3   7   2  | 6   4    8 | 5  1 9  |
 +------------+------------+---------+
 | 2   6   1  | 89  89   7 | 3  4 5  |
 | 4   5   3  | 1   6    2 | 8  9 7  |
 | 9   8   7  | 4   5    3 | 1  6 2  |
 +------------+------------+---------+
 
 | 
 Play this puzzle online at the Daily Sudoku site
 
 This one's quite neat compared to the frequent bland fare:
 There are two XY-Wings that end in the same elimination-
 69-3 pivot at r3c9 and 46-9 on r1c7,pivot r4c7,r4c2 both
 lead to r1c2=3. Unfortunately this doesn't lead to a stte conclusion.
 But what's this?
 is a one-stepper. 	  | Quote: |  	  | the other 46-9 on r2c7,pivot (again!) r4c7 r4c2 r2c3=8 | 
 
 Two XYs with the same numbers and same pivot- one does it and
 the other doesn't. Classic.
 
 Hugh
   (select the white space under Quote to see the solution)
 | 
 
 Hugh,I have a couple of comments.
 
 
  	  | Quote: |  	  | 69-3 pivot at r3c9 | 
 There is a 69-3 pivoted in r1c7 and nothing pivoted in r3c9 that I can see.
 
 
  	  | Quote: |  	  | 46-9 on r1c7,pivot r4c7,r4c2 | 
 What does "onr1c7" mean?
 
 I think if all three cells are mentioned it would be clearer to say 46-9 pivoted at r4c7with pincers at r1c7 and r4c2
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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Thu Jun 02, 2016 1:51 pm    Post subject: June 2 |   |  
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				| 869 also a one-step solution. 
 Early Earl
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		| RobertRattley 
 
 
 Joined: 24 Jun 2007
 Posts: 118
 Location: Australia
 
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				|  Posted: Thu Jun 02, 2016 1:56 pm    Post subject: |   |  
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				| I was a bit surprised to see all the discussion since I spotted only 2 xy wings (but then I didn't try hard to find more).  One of them I found was neither sufficient nor necessary, and the other, leading to a solution, is the one Earl mentioned: 
 xy wing 689 pivot r1c1 pincers r1c7 and 2rc3.
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		| dongrave 
 
 
 Joined: 06 Mar 2014
 Posts: 572
 
 
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				|  Posted: Fri Jun 03, 2016 12:05 am    Post subject: |   |  
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				| Great puzzle!  No wonder there was so much confusion.  I found 6 wings (most have already been listed).  A couple of them look like they solve it and the others look like they don't. 
 There's a 68-9 XY Wing with pivot at r1c1 and pincers at r1c7 and r2c3 so r1c2,r2c7<>9; a 69-3 XY Wing with pivot at r1c7 and pincers at r1c2 and r3c9 so r3c2<>3; an 89-6 XY Wing with pivot at r2c3 and pincers at r1c1 and r4c3 so r5c1<>6; a 789 XYZ Wing with pivot at r2c4 and pincers at r2c3 and r4c4 so r2c5<>9; and TWO 46-9 XY Wings with pivot at r4c7 - one with pincers at r1c7 and r4c2 (so r1c2<>9) and the other with pincers at r2c7 and r4c3 (so r2c3<>9).  Good one!
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		| hughwill 
 
 
 Joined: 05 Apr 2010
 Posts: 424
 Location: Birmingham UK
 
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				|  Posted: Fri Jun 03, 2016 11:14 pm    Post subject: Re: Jun 2 VH |   |  
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				|  	  | Marty R. wrote: |  	  | 
 Hugh,I have a couple of comments.
 
 
  	  | Quote: |  	  | 69-3 pivot at r3c9 | 
 There is a 69-3 pivoted in r1c7 and nothing pivoted in r3c9 that I can see.
 
 
  	  | Quote: |  	  | 46-9 on r1c7,pivot r4c7,r4c2 | 
 What does "onr1c7" mean?
 
 I think if all three cells are mentioned it would be clearer to say 46-9 pivoted at r4c7with pincers at r1c7 and r4c2
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 Marty- yes, wrong pivot. Forgot the 'pincers' term - not seen it for some while
 and age plays havoc with the memory.
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sat Jun 04, 2016 3:27 pm    Post subject: |   |  
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				|  	  | Quote: |  	  | and age plays havoc with the memory. | 
 Hugh, I'm well (too well, actually) acquainted with the infirmities of age.
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