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		| hughwill 
 
 
 Joined: 05 Apr 2010
 Posts: 424
 Location: Birmingham UK
 
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				|  Posted: Thu Nov 05, 2015 10:37 am    Post subject: Nov 5 "VH" |   |  
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				| No fireworks* today I'm afraid: I think this is one of the few puzzles that comes up as VH but isn't.
 In the diagram (after basics only):
 
  	  | Code: |  	  | +-----------------+------------+------------+
 | 9   3     256   | 8  568 12  | 125 7   4  |
 | 8   7     245   | 12 45  3   | 9   16  26 |
 | 1   256   2456  | 7  456 9   | 25  3   8  |
 +-----------------+------------+------------+
 | 7   1     3     | 4  2   6   | 8   9   5  |
 | 5   4     8     | 9  3   7   | 6   2   1  |
 | 26  26    9     | 5  1   8   | 7   4   3  |
 +-----------------+------------+------------+
 | 246 268   1267  | 3  78  5   | 124 168 9  |
 | 24  289   12    | 6  89  124 | 3   5   7  |
 | 3   25689 12567 | 12 789 124 | 124 168 16 |
 +-----------------+------------+------------+
 
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 (Play this puzzle online at the Daily Sudoku site)
 
 check the difficulty by pressing 'Grade'. Then, using the triple 124 on r9 set
 r9c9 to 6. Check Grade again.
 
 I think these are so rare that they have their own interest though obviously
 there's a small bug in the algorithm. Working out what that was would be a
 good puzzle I bet! I'm not complaining- Sam's left us with a pretty good
 website which has worked well for me for years......
 
 Hugh
 *UK readers only
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		| Rocky Mozell 
 
 
 Joined: 28 Jul 2010
 Posts: 34
 Location: Boston, MA
 
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				|  Posted: Thu Nov 05, 2015 3:06 pm    Post subject: |   |  
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				| I see what you did there. |  | 
	
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		| dongrave 
 
 
 Joined: 06 Mar 2014
 Posts: 572
 
 
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				|  Posted: Thu Nov 05, 2015 9:37 pm    Post subject: |   |  
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				| Hi Hugh, I think there's something wrong with your grid!  I had a 26 in r9c9; not 16!  In fact, you can't have a 16 there because of the 1 in r5c9.  Then, after you fix that, there is no solution (I think) from the triple in r9 and instead I used the X-Wing on 2's in columns 4 and 9 which solves it. |  | 
	
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		| dongrave 
 
 
 Joined: 06 Mar 2014
 Posts: 572
 
 
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				|  Posted: Thu Nov 05, 2015 10:41 pm    Post subject: |   |  
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				| Hey Hugh, I just looked at it a second time and even though you have 12 in r9c9 instead of 26, the triple in r9 does solve it!  I'll be darned!  Good one Hugh! |  | 
	
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		| kuskey 
 
 
 Joined: 10 Dec 2008
 Posts: 141
 Location: Pembroke, NH
 
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				|  Posted: Thu Nov 05, 2015 10:56 pm    Post subject: 5 Nov VH |   |  
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				| dongrave at last finds concensus, at least with me. No one has yet said the puzzle is solved by basics only, but it's true.  I've solved it three times with basics only and I think dongrave agrees. 
 degree of difficulty is another matter
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Thu Nov 05, 2015 11:31 pm    Post subject: |   |  
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				| Yes the 124 triple solves it. I  missed it on paper and used the X-Wing. But using the Draw/Play the triple does the job. |  | 
	
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		| hughwill 
 
 
 Joined: 05 Apr 2010
 Posts: 424
 Location: Birmingham UK
 
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				|  Posted: Fri Nov 06, 2015 10:05 am    Post subject: |   |  
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				|  	  | dongrave wrote: |  	  | Hi Hugh, I think there's something wrong with your grid!  I had a 26 in r9c9; not 16!  In fact, you can't have a 16 there because of the 1 in r5c9.  Then, after you fix that, there is no solution (I think) from the triple in r9 and instead I used the X-Wing on 2's in columns 4 and 9 which solves it. | 
 
 My mistake in reverting to 16 rather than 26 after solving. I must be more
 careful in future....
 
 
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		| dongrave 
 
 
 Joined: 06 Mar 2014
 Posts: 572
 
 
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				|  Posted: Fri Nov 06, 2015 12:19 pm    Post subject: |   |  
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				| Darn it all kuskey!  Tricked twice on the same day!  First, Sammy's program tells me that the puzzle's very hard.  Then Hugh deliberately puts the wrong candidates in r9c9 to mislead me!  Ugh.  What a day!  |  | 
	
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