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		| ZeroAssoluto 
 
 
 Joined: 05 Feb 2017
 Posts: 1019
 Location: Rimini, Italy
 
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				|  Posted: Fri Sep 17, 2021 8:12 am    Post subject: Sep 17 VH |   |  
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				| Hi everyone 
 
  	  | Code: |  	  | +----------------+--------------+------------+
 | 23689 269  389 | 4  7    25   | 18 158 19  |
 | 4     29   89  | 1  25   3    | 6  578 79  |
 | 1     7    5   | 9  6    8    | 3  4   2   |
 +----------------+--------------+------------+
 | 289   1    489 | 5  234  24   | 7  68  36  |
 | 5     3    6   | 78 19   79   | 18 2   4   |
 | 28    24   7   | 38 1234 6    | 5  9   13  |
 +----------------+--------------+------------+
 | 7     8    2   | 6  49   1    | 49 3   5   |
 | 369   4569 1   | 2  3459 4579 | 49 67  8   |
 | 369   4569 349 | 37 8    4579 | 2  167 167 |
 +----------------+--------------+------------+
 
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 Play this puzzle online at the Daily Sudoku site
 
 XY-Wing 1,3,8 in r5c7,r6c49 and -8 in r5c4
 
 Ciao Gianni
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		| TomC 
 
 
 Joined: 30 Oct 2020
 Posts: 359
 Location: Wales
 
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				|  Posted: Sat Sep 18, 2021 6:08 am    Post subject: |   |  
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				|  	  | Code: |  	  | +------------------+----------------+------------+
 | 23689  269   389 | 4   7     25   | 18 158 19  |
 | 4      29    89  | 1   25    3    | 6  578 79  |
 | 1      7     5   | 9   6     8    | 3  4   2   |
 +------------------+----------------+------------+
 | 289    1     489 | 5   234*  24*  | 7  68  36  |
 | 5      3     6   | 78  19    79   | 18 2   4   |
 | 28*    24*   7   | 38* 1234  6    | 5  9   13  |
 +------------------+----------------+------------+
 | 7      8     2   | 6   49    1    | 49 3   5   |
 | 369    4569  1   | 2   3459  4579 | 49 67  8   |
 | 369    4569  349 | 37  8     4579 | 2  167 167 |
 +------------------+----------------+------------+
 
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 Not sure what this is, but the 5 * cells (containing 2348) form a pattern which eliminates 24 from r6c5 and solves the puzzle
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		| TomC 
 
 
 Joined: 30 Oct 2020
 Posts: 359
 Location: Wales
 
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				|  Posted: Sat Sep 18, 2021 6:39 am    Post subject: |   |  
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				| And it can eliminate 2 and 4 from r4c13 |  | 
	
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		| Mogulmeister 
 
 
 Joined: 03 May 2007
 Posts: 1151
 
 
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				|  Posted: Sat Sep 18, 2021 8:42 am    Post subject: |   |  
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 Nicely done Tom. One way of explaining this (others exist I am sure) is an ALS with two digit eliminations which is reasonably rare.
 
 Set A {2,3,4,8}
 Set B {2,3,4}
 
 
 The restricted common digit is 3 (r4c5,r6c4)
 
 The 2's and 4's in red can see all the other 2's and 4's in A & B so are eliminated. These are the common candidates.
 
 Good spot!
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		| Mogulmeister 
 
 
 Joined: 03 May 2007
 Posts: 1151
 
 
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				|  Posted: Sat Sep 18, 2021 9:39 am    Post subject: |   |  
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				| I guess you could also view this as a slightly unconventional WXYZ wing - the 4 candidates are in 5 cells. You can view the <38> in r6c4 as a hinge.
 
 If it’s 3 then you create a <24> locked pair in r4c56 eliminating all the 2s and 4s in the red cells.
 
 If it’s 8 then r6c12 become 2 and 4 making the same eliminations as above.
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		| TomC 
 
 
 Joined: 30 Oct 2020
 Posts: 359
 Location: Wales
 
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				|  Posted: Sat Sep 18, 2021 9:59 am    Post subject: |   |  
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				| Indeed, many ways to describe this. 
 My first thought was to say that if r6c5 is either 2 or 4 then r6c4 would always be 3 leading to a contradiction in box 5
 
 I then noticed the other elimination of 24's in box 4
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		| Mogulmeister 
 
 
 Joined: 03 May 2007
 Posts: 1151
 
 
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				|  Posted: Sat Sep 18, 2021 10:50 am    Post subject: |   |  
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				| Also a contradiction with the 
 ANP (24=3)r4c56-(3=8)r6c4 etc etc
 
 Which puts a contradictory 3 in r4c9.
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