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		| gohast 
 
 
 Joined: 26 Sep 2006
 Posts: 18
 Location: Dublin, Ireland
 
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				|  Posted: Tue Apr 01, 2008 11:34 pm    Post subject: Wed Apr 2 VH |   |  
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				| A type 4 UR and then an XY wing. Enjoyed that! |  | 
	
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		| prakash 
 
 
 Joined: 02 Jan 2008
 Posts: 67
 Location: New Jersey, USA
 
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				|  Posted: Tue Apr 01, 2008 11:41 pm    Post subject: |   |  
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				| Very straightforward, The the 148 XY wing cracks the puzzle wide open. Still don't see the UR 
  	  | Code: |  	  | +------------+--------------+-------------+
 | 258 158 3  | 18  4    9   | 7   28  6   |
 | 48  67  67 | 2   35   35  | 489 1   49  |
 | 248 9   14 | 168 168  7   | 3   248 5   |
 +------------+--------------+-------------+
 | 489 68  69 | 478 278  24  | 1   5   3   |
 | 3   2   14 | 5   18   6   | 48  9   7   |
 | 7   18  5  | 9   1238 234 | 6   24-8 24 |
 +------------+--------------+-------------+
 | 1   3   8  | 47  257  245 | 249 6   249 |
 | 59  57  79 | 46  26   8   | 24  3   1   |
 | 6   4   2  | 3   9    1   | 5   7   8   |
 +------------+--------------+-------------+
 
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		| Kdelle 
 
 
 Joined: 20 Mar 2008
 Posts: 59
 Location: Hudson, NH
 
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				|  Posted: Wed Apr 02, 2008 5:26 am    Post subject: |   |  
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				| I'm not familiar with all the URs, but I think there's one on 49 in R27C79. |  | 
	
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		| nataraj 
 
 
 Joined: 03 Aug 2007
 Posts: 1048
 Location: near Vienna, Austria
 
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				|  Posted: Wed Apr 02, 2008 5:53 am    Post subject: |   |  
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				|  	  | prakash wrote: |  	  | Very straightforward, The the 148 XY wing cracks the puzzle wide open. | 
 
 I agree. BTW, The xy wing solves r6c8=4 immediately, since 2 in col 8 is confined to box 1.
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		| ravel 
 
 
 Joined: 21 Apr 2006
 Posts: 536
 
 
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				|  Posted: Wed Apr 02, 2008 10:35 am    Post subject: |   |  
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				| Funny, its the same i had in the "Other puzzles" forum today. 	  | Kdelle wrote: |  	  | I'm not familiar with all the URs, but I think there's one on 49 in R27C79. | 
 
  	  | Code: |  	  | +------------+--------------+-------------+ | 258 158 3  | 18  4    9   | 7   28  6   |
 | 48  67  67 | 2   35   35  |#489 1  #49  |
 | 248 9   14 | 168 168  7   | 3   248 5   |
 +------------+--------------+-------------+
 | 489 68  69 | 478 278  24  | 1   5   3   |
 | 3   2   14 | 5   18   6   | 48  9   7   |
 | 7   18  5  | 9   1238 234 | 6   248 24 |
 +------------+--------------+-------------+
 | 1   3   8  | 47  257  245 |#249 6  #249 |
 | 59  57  79 | 46  26   8   | 24  3   1   |
 | 6   4   2  | 3   9    1   | 5   7   8   |
 +------------+--------------+-------------+
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 Because 9 is an x-wing, you can eliminate 4 from r7c7 (it would imply that both r2c7 and r7c9 are 9 and r2c9 4 again).
 Since r2c7=4 implies r7c9=4 (via r78c7<>4) and thus r7c7=9 and r2c9=9, 4 can be eliminated from r2c7 also.
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		| cgordon 
 
 
 Joined: 04 May 2007
 Posts: 769
 Location: ontario, canada
 
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				|  Posted: Wed Apr 02, 2008 12:22 pm    Post subject: |   |  
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				| A jolly good sudoku!! 
 I found an ER solution using the two 4s in C2 and the hinge in Box 6. This gets rid of the 4 in R3C8.
 
 After that: -  "Bob's your uncle".
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		| sdq_pete 
 
 
 Joined: 30 Apr 2007
 Posts: 119
 Location: Rotterdam, NL
 
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				|  Posted: Wed Apr 02, 2008 2:41 pm    Post subject: |   |  
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				| According to my Uncle Bob, there's a simple X-wing on 2's eliminating 2 from R6C8, and it was pretty plain sailing after that too. 
 Peter
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		| TexCat 
 
 
 Joined: 07 Jul 2006
 Posts: 32
 
 
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				|  Posted: Wed Apr 02, 2008 3:34 pm    Post subject: |   |  
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				| My Uncle Bob found the 18 w-wing pretty quickly and then it was as easy as Aunt Sue's pie. |  | 
	
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Wed Apr 02, 2008 3:47 pm    Post subject: |   |  
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				| I used the W-Wing on 18 and the Type 1 UR on 49. |  | 
	
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		| ravel 
 
 
 Joined: 21 Apr 2006
 Posts: 536
 
 
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				|  Posted: Wed Apr 02, 2008 4:23 pm    Post subject: |   |  
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				| Just saw now, that in prakash's grid, which i had looked at for the UR, the 2 can be placed in r6c9, because it is locked to box 3 in column 8. Then you have the type 4 UR with the same eliminations as above (r27c8<>4) |  | 
	
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		| Victor 
 
 
 Joined: 29 Sep 2005
 Posts: 207
 Location: NI
 
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				|  Posted: Wed Apr 02, 2008 4:58 pm    Post subject: |   |  
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				| Or, type 4 followed by colouring in 4s to eliminate the 4 in r3c8: but the ER is nicer.  & I think that's capped by the W-wing. |  | 
	
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		| storm_norm 
 
 
 Joined: 18 Oct 2007
 Posts: 1741
 
 
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				|  Posted: Wed Apr 02, 2008 7:42 pm    Post subject: |   |  
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				| xy-wing {1,4,8}  for me as well.  was a little distracted because Ms. Clinton was in town today and was keeping an ear to the scanner as she was speaking at york college, only a block from my childhood neighborhood. 
 26 min online time to complete.
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