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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Thu Oct 15, 2009 10:09 pm    Post subject: Decabit Insane October 15 |   |  
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				| For me, the first move was the hardest. 
 
  	  | Code: |  	  | +-------+-------+-------+
 | . . 7 | 3 . . | . . . |
 | . . . | . 8 4 | . 5 . |
 | 4 . 5 | . . . | 7 8 . |
 +-------+-------+-------+
 | . 8 . | . . 5 | 2 . . |
 | . . 3 | 4 . 8 | . . . |
 | 2 . . | . . . | . . . |
 +-------+-------+-------+
 | . . . | . . 6 | . 4 2 |
 | . . . | . . . | 1 . 7 |
 | . 1 . | . . 3 | . 6 5 |
 +-------+-------+-------+
 
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 Play this puzzle online at the Daily Sudoku site
 Ted
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		| storm_norm 
 
 
 Joined: 18 Oct 2007
 Posts: 1741
 
 
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				|  Posted: Thu Oct 15, 2009 11:49 pm    Post subject: |   |  
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				|  	  | Code: |  	  | .------------------------.------------------------.------------------------. | 8       69      7      | 3       5       19     | 469     2       1469   |
 | 1369    2369    1269   | 7       8       4      | 369     5       369    |
 | 4       39      5      | 269     69      129    | 7       8       139    |
 :------------------------+------------------------+------------------------:
 | 1679    8       1469   | 169     1369    5      | 2       1379    3469   |
 | 15679   5679    3      | 4       2       8      | 569     179     69     |
 | 2       4569    1469   | 169     1369    7      | 34569   139     8      |
 :------------------------+------------------------+------------------------:
 | 3579    3579    89     | 1589    179     6      | 389     4       2      |
 | 3569    234569  24689  | 2589    49     *29     | 1       39      7      |
 | 79      1       2489   |*289     479     3      |*89      6       5      |
 '------------------------'------------------------'------------------------'
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 xyz-wing removes 9 from r9c5
 
 
  	  | Code: |  	  | +-----------------------+-------------------+-------------------+ | 8      69      7      | 3       5     19  | 469    2     1469 |
 | 1369   2369    1269   | 7       8     4   | 369    5     369  |
 | 4      39      5      | 269     69    129 | 7      8     139  |
 +-----------------------+-------------------+-------------------+
 | 1679   8       1469   | 169     1369  5   | 2      1379  3469 |
 | 15679  5679    3      | 4       2     8   | 569    179   69   |
 | 2      4569    1469   | 169     1369  7   | 34569  139   8    |
 +-----------------------+-------------------+-------------------+
 | 3579   3579    89     | 1589    179   6   | 389    4     2    |
 | 3569   234569  24689  | 2589    (49)  29  | 1      39    7    |
 | 79     1       89(24) | 8-9(2)  7(4)  3   | 89     6     5    |
 +-----------------------+-------------------+-------------------+
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 (9=4)r8c5 - (4)r9c5 = (4-2)r9c3 = (2)r9c4; r9c4 <> 9
 
 
  	  | Code: |  	  | +----------------------+------------------+-------------------+ | 8      69      7     | 3     5     19   | 469    2     1469 |
 | 1369   2369    1269  | 7     8     4    | 369    5     369  |
 | 4      39      5     | 269   69    129  | 7      8     139  |
 +----------------------+------------------+-------------------+
 | 1679   8       1469  | 169   1369  5    | 2      1379  3469 |
 | 15679  5679    3     | 4     2     8    | 569    179   69   |
 | 2      4569    1469  | 169   1369  7    | 34569  139   8    |
 +----------------------+------------------+-------------------+
 | 3579   3579    89    | 1589  179   6    | 389    4     2    |
 | 3569   234569  24689 | 2589  49    (29) | 1      3-9   7    |
 | 79     1       2489  | (28)  47    3    | (89)   6     5    |
 +----------------------+------------------+-------------------+
 | 
 xy-wing finishes {2,8,9}
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Fri Oct 16, 2009 11:36 am    Post subject: |   |  
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				| I also had three moves to complete this puzzle. 
 The first move was the xyz-wing noted by Norm; it took me a while to spot it and I did not find any other VH type moves. This step deleted the 9 from r9c5, which opened up a
 xy-wing 47-9 with vertex 47 in r9c5 and pincers in r8c5 & r9c1 which deleted the 9 in r9c4, which was the same as Norm's short chain, plus the 9s in r8c123. This move then opened up a
 xy-wing 28-9, which again was identical to the move by Norm.
 
 I wonder if this puzzle has other VH solutions
   
 Ted
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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Fri Oct 16, 2009 2:56 pm    Post subject: insane |   |  
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				| If you use the 479 xyz-wing to remove 9 from R9C4, it opens a 289 xy-wing, solving the puzzle in two steps. 
 Earl
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Fri Oct 16, 2009 5:08 pm    Post subject: Re: insane |   |  
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				|  	  | Earl wrote: |  	  | If you use the 479 xyz-wing to remove 9 from R9C4, it opens a 289 xy-wing, solving the puzzle in two steps. 
 Earl
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 Very nice Earl
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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Fri Oct 16, 2009 9:00 pm    Post subject: |   |  
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				| Did you notice that, after basics, EVERY unsolved cell could be 9?  In other words, no solved cells are 9. 
 Keith
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sat Oct 17, 2009 4:24 am    Post subject: |   |  
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				| I noticed that with the 9s. I also used eight moves. Then I noticed a triple which may have been there before the moves, but, what the heck, I finished it.    |  | 
	
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Sat Oct 17, 2009 4:45 am    Post subject: |   |  
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				|  	  | Marty R. wrote: |  	  | I noticed that with the 9s. I also used eight moves. Then I noticed a triple which may have been there before the moves, but, what the heck, I finished it.    | 
 
 Well Marty, you answered my question: Yes this puzzle has multiple VH solutions.
 
 Ted
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		| wapati 
 
 
 Joined: 10 Jun 2008
 Posts: 472
 Location: Brampton, Ontario, Canada.
 
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				|  Posted: Sat Oct 17, 2009 7:04 am    Post subject: |   |  
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				|  	  | tlanglet wrote: |  	  | I wonder if this puzzle has other VH solutions
   Ted
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 What are the VH methods?
 
 Is there a listing on-site?
 
 Thanks.
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		| nataraj 
 
 
 Joined: 03 Aug 2007
 Posts: 1048
 Location: near Vienna, Austria
 
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				|  Posted: Sat Oct 17, 2009 11:38 am    Post subject: |   |  
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				|  	  | wapati wrote: |  	  | What are the VH methods? 
 Is there a listing on-site?
 
 Thanks.
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 Don't know about a listing. Also, I think what is meant by "VH methods" is really "methods to solve this site's VH puzzles". And to that question, the answer (from my experience)  is:
 
 
 To solve "Very Hard" puzzles from dailysudoku.com, you need nothing more than x-wing, xy-wing and xyz-wing
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		| wapati 
 
 
 Joined: 10 Jun 2008
 Posts: 472
 Location: Brampton, Ontario, Canada.
 
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				|  Posted: Sat Oct 17, 2009 10:56 pm    Post subject: |   |  
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				|  	  | nataraj wrote: |  	  |  	  | wapati wrote: |  	  | What are the VH methods? 
 Is there a listing on-site?
 
 Thanks.
 | 
 
 Don't know about a listing. Also, I think what is meant by "VH methods" is really "methods to solve this site's VH puzzles". And to that question, the answer (from my experience)  is:
 
 
 To solve "Very Hard" puzzles from dailysudoku.com, you need nothing more than x-wing, xy-wing and xyz-wing
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 Thanks.
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