| View previous topic :: View next topic   | 
	
	
	
		| Author | 
		Message | 
	
	
		tlanglet
 
 
  Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
  | 
		
			
				 Posted: Thu Nov 18, 2010 3:25 pm    Post subject: Vanhagen Extreme Nov 18 | 
				     | 
			 
			
				
  | 
			 
			
				Another Vanhegan that seems to have numerous chains.....
 
 
 	  | Code: | 	 		  
 
+-------+-------+-------+
 
| 2 . . | 5 . . | 6 . 4 |
 
| . 1 7 | 6 . . | . 5 . |
 
| 9 . . | . . 4 | . 8 . |
 
+-------+-------+-------+
 
| . . 8 | . . . | . 3 2 |
 
| . . . | . 4 . | . . . |
 
| 1 3 . | . . . | 7 . . |
 
+-------+-------+-------+
 
| . 2 . | 7 . . | . . 5 |
 
| . 6 . | . . 1 | 3 2 . |
 
| 3 . 5 | . . 2 | . . 7 |
 
+-------+-------+-------+
 
 | 	  
 
Play this puzzle online at the Daily Sudoku site 
 
 
 	  | Quote: | 	 		  (6=9)r4c5-r7c5=r7c78-(9=8)r8c9-r9c7=(8-5)r5c7=r4c7-(5=6)r4c1; r4c6<>6
 
 
(3=2)r3c4-(2=1)r3c7-r9c7=(1-6)r9c8=r7c8-(6=3)r7c6; r2c6<>3
 
 
Kraken cell (249)r6c3; r4c2<>9
 
(2)r6c2-(2=9)r5c3;
 
||
 
(4)r6c3-(4=9)r6c8-(9=1)r5c8-r9c8=(1-8)r9c7=r8c9-r56c9=(8-5)r5c7=r4c7-(5=6)r4c1-(6=9)r4c5;
 
||
 
(9)r6c3;
 
 
AXY-wing -369 vertex (69)r4c5, pincers (36)r5c6 & (39)r7c5 with fin (6)r7c5; r7c6<>3
 
xy-wing =(6)r7c5-(6=8)r9c5-(8=1)r9c7-(1=2)r3c7-(2=3)r3c4-r5c4=(3)r5c6 | 	  
 
Ted | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
  | 
		
			
				 Posted: Thu Nov 18, 2010 5:39 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				I often have trouble with Vanhegan extremes, but this wasn't one of them. I did it a second time because I didn't trust myself.
 
 
 	  | Quote: | 	 		  | XYZ-Wing (369); r9c5<>6 | 	 
  | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		keith
 
 
  Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
  | 
		
			
				 Posted: Thu Nov 18, 2010 6:27 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				Marty beat me to it!  After basics: 	  | Code: | 	 		  +-------------------+-------------------+-------------------+
 
| 2     8     3     | 5     1     9     | 6     7     4     | 
 
| 4     1     7     | 6     238   38    | 29    5     39    | 
 
| 9     5     6     | 23    7     4     | 12    8     13    | 
 
+-------------------+-------------------+-------------------+
 
| 56    479   8     | 19    69    67    | 1459  3     2     | 
 
| 56    79    29    | 12389 4     3678  | 1589  19    1689  | 
 
| 1     3     249   | 289   2689  5     | 7     49    689   | 
 
+-------------------+-------------------+-------------------+
 
| 8     2     1     | 7     369   36    | 49    469   5     | 
 
| 7     6     49    | 489   5     1     | 3     2     89    | 
 
| 3     49    5     | 489   689   2     | 189   169   7     | 
 
+-------------------+-------------------+-------------------+ | 	  Keith | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		peterj
 
 
  Joined: 26 Mar 2010 Posts: 974 Location: London, UK
  | 
		
			
				 Posted: Thu Nov 18, 2010 6:36 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				I missed the xyz-wing - I think the "Extreme" rating sent me looking at chains too early..  (Nice spot, Marty    )
 
 
Here's an ANP that also solves it..
 
 	  | Quote: | 	 		  ANP(49=6)r7c78 - (6=3)r7c6 - r7c5=r2c5 - (3=9)r2c9 ; r8c9<>9
 
 
.. or written as a w-wing (for fun)...
 
w-wing(39)/als ; (946=3)r7c678 - r7c5=r2c5 - (3=9)r2c9
 
 | 	 
  | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		daj95376
 
 
  Joined: 23 Aug 2008 Posts: 3854
 
  | 
		
			
				 Posted: Thu Nov 18, 2010 7:33 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				Using Keith's grid and reviewing Peter's chain:
 
 
 	  | Code: | 	 		  +-------------------+-------------------+-------------------+
 
| 2     8     3     | 5     1     9     | 6     7     4     |
 
| 4     1     7     | 6     238   38    | 29    5     39    |
 
| 9     5     6     | 23    7     4     | 12    8     13    |
 
+-------------------+-------------------+-------------------+
 
| 56    479   8     | 19    69    67    | 1459  3     2     |
 
| 56    79    29    | 12389 4     3678  | 1589  19    1689  |
 
| 1     3     249   | 289   2689  5     | 7     49    689   |
 
+-------------------+-------------------+-------------------+
 
| 8     2     1     | 7     369   36    | 49    469   5     |
 
| 7     6     49    | 489   5     1     | 3     2     89    |
 
| 3     49    5     | 489   689   2     | 189   169   7     |
 
+-------------------+-------------------+-------------------+
 
 
ANP(49=6)r7c78 - (6=3)r7c6 - r7c5=r2c5 - (3=9)r2c9 ; r8c9<>9
 
 | 	  
 
I had a feeling that an alternate perspective existed. Finally, it hit me:
 
 
 	  | Code: | 	 		  (9)r7c78 = (9-3)r7c5 = r2c5 - (3=9)r2c9 ; r8c9<>9
 
 | 	  
 
Which is the "reverse" of an M-Wing Type 3A.
 
 
 
 
Yes, Congratulations Marty on finding that solitary XYZ-Wing! | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		 |