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		| dongrave 
 
 
 Joined: 06 Mar 2014
 Posts: 572
 
 
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				|  Posted: Thu Dec 10, 2015 3:52 am    Post subject: I don't see it... |   |  
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				| I've been practicing finding chains lately for Evil puzzles on 1sudoku.com and I don't see one for the following puzzle.  Could someone help me out?  I'm sick of looking at it - even though I have this feeling that it's probably as obvious as a big fish lurking in the weeds.  Thanks, Don. 
  	  | Code: |  	  | nš59271 Evil
 +-------+-------+-------+
 | 6 . . | 3 9 1 | . . . |
 | . 9 . | . . . | . . . |
 | . . 3 | 4 6 . | 8 . . |
 +-------+-------+-------+
 | 3 . 2 | . . . | . . 5 |
 | 5 . 9 | . 8 . | 2 . 6 |
 | 7 . . | . . . | 4 . 9 |
 +-------+-------+-------+
 | . . 6 | . 3 2 | 9 . . |
 | . . . | . . . | . 5 . |
 | . . . | 1 7 8 | . . 2 |
 +-------+-------+-------+
 
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		| JC Van Hay 
 
 
 Joined: 13 Jun 2010
 Posts: 494
 Location: Charleroi, Belgium
 
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				|  Posted: Thu Dec 10, 2015 8:49 am    Post subject: |   |  
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				| Hint : after "basics", {R3, R9, C1} has 2 solutions -> either a contradiction or singles to a unique solution. |  | 
	
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		| bat999 
 
 
 Joined: 09 Jul 2015
 Posts: 55
 Location: UK
 
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				|  Posted: Thu Dec 10, 2015 9:41 pm    Post subject: |   |  
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				| (4=5)r9c278 - (5=7)r3c129 - r2c8 = (7)r7c8 => -4 r7c8; stte 	  | Code: |  	  | .----------------.------------.-------------------. |  6    78   478 | 3   9  1   |  5     2     47   |
 |  14   9    457 | 8   2  57  |  136  c467   1347 |
 | b12  b25   3   | 4   6  57  |  8     9    b17   |
 :----------------+------------+-------------------:
 |  3    46   2   | 69  1  469 |  7     8     5    |
 |  5    14   9   | 7   8  34  |  2     13    6    |
 |  7    168  18  | 2   5  36  |  4     13    9    |
 :----------------+------------+-------------------:
 |  48   17   6   | 5   3  2   |  9    d7-4   1478 |
 |  28   23   17  | 69  4  69  |  13    5     1378 |
 |  9   a35   45  | 1   7  8   | a36   a46    2    |
 '----------------'------------'-------------------'
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		| dongrave 
 
 
 Joined: 06 Mar 2014
 Posts: 572
 
 
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				|  Posted: Thu Dec 10, 2015 10:59 pm    Post subject: |   |  
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				| Oh, good one!  No wonder I didn't see it.  And that looks like the one that JC was referring to too.  Even with the hint I missed it.  Thanks guys, that wasn't obvious to me.  Don. |  | 
	
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