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		| daj95376 
 
 
 Joined: 23 Aug 2008
 Posts: 3854
 
 
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				|  Posted: Fri Mar 19, 2010 11:49 pm    Post subject: Puzzle 10/03/19 (B) |   |  
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				|  	  | Code: |  	  | +-----------------------+ | 2 9 . | . . 8 | . . . |
 | 1 . 3 | . 9 7 | . 2 6 |
 | . 7 . | . . . | 5 . . |
 |-------+-------+-------|
 | . . . | 2 . . | 7 . . |
 | . 6 . | . . . | . . . |
 | 7 1 . | . . 6 | . 5 . |
 |-------+-------+-------|
 | . . 7 | 8 . . | 2 . . |
 | . 3 . | . . 2 | . 9 5 |
 | . 2 . | . . . | . 1 . |
 +-----------------------+
 
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 Play this puzzle online at the Daily Sudoku site
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Sat Mar 20, 2010 2:18 am    Post subject: |   |  
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				| An interesting one stepper. 
 Type 2 UR 46 in r18c45. As a type 2 UR, a 7 must go into r8c45, but this does not provide any deletions since row8 and box8 do not contain any other digit 7s.
 
 However, looking at the implications outside the UR, we find that no other digits 4 or 6 occur in row1 but in row8 a 6 must occur in col17 or a 4 must occur in col1. Using this strong inference we get: UR 46 [(6)r8c17 = (4)r8c1)]r18c45 - (4=6)r9c3 - r9c7 = r8c7; r8c45<>6
 
 Ted
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		| arkietech 
 
 
 Joined: 31 Jul 2008
 Posts: 1834
 Location: Northwest Arkansas USA
 
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				|  Posted: Sat Mar 20, 2010 8:28 am    Post subject: |   |  
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				| an ALS solves it in one step also:  	  | Code: |  	  | *-----------------------------------------------------------------------------* | 2       9       5       | 46      46      8       | 13      7       13      |
 | 1       8       3       | 5       9       7       | 4       2       6       |
 | 46      7       46      | 13      2       13      | 5       8       9       |
 |-------------------------+-------------------------+-------------------------|
 | 35      4       89      | 2       1358    1359    | 7       6       138     |
 | 35      6       289     | 13479   134578  13459   | 139     34      12348   |
 | 7       1       289     | 349     348     6       | 39      5       2348    |
 |-------------------------+-------------------------+-------------------------|
 | 69      5       7       | 8       16      19      | 2       34      34      |
 | 68-4    3       1       |a467    a467     2       |a68      9       5       |
 | 4689    2      b46      | 369-4   356-4   359-4   |b68      1       7       |
 *-----------------------------------------------------------------------------*
 ALS
 A=4678
 B=468
 X=8 c7
 Z=4
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sun Mar 21, 2010 12:33 am    Post subject: |   |  
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				| I'll go with a four-stepper. 
 Type 1 UR (46)
 Type 4 UR (68) utilizing a cell from which 6 had been removed by prior step
 XY-Wing (486) with pincer transport
 X-Wing (4)
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Sun Mar 21, 2010 1:32 pm    Post subject: |   |  
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				|  	  | arkietech wrote: |  	  | an ALS solves it in one step also:  	  | Code: |  	  | *-----------------------------------------------------------------------------* | 2       9       5       | 46      46      8       | 13      7       13      |
 | 1       8       3       | 5       9       7       | 4       2       6       |
 | 46      7       46      | 13      2       13      | 5       8       9       |
 |-------------------------+-------------------------+-------------------------|
 | 35      4       89      | 2       1358    1359    | 7       6       138     |
 | 35      6       289     | 13479   134578  13459   | 139     34      12348   |
 | 7       1       289     | 349     348     6       | 39      5       2348    |
 |-------------------------+-------------------------+-------------------------|
 | 69      5       7       | 8       16      19      | 2       34      34      |
 | 68-4    3       1       |a467    a467     2       |a68      9       5       |
 | 4689    2      b46      | 369-4   356-4   359-4   |b68      1       7       |
 *-----------------------------------------------------------------------------*
 ALS
 A=4678
 B=468
 X=8 c7
 Z=4
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 Dan, very nice find
   
 Ted
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