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		arkietech
 
 
  Joined: 31 Jul 2008 Posts: 1834 Location: Northwest Arkansas USA
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				 Posted: Thu Feb 09, 2012 10:49 pm    Post subject: patterns game by joel64 Dec 06, 2010 | 
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				 	  | Code: | 	 		   *-----------*
 
 |1..|...|2..|
 
 |...|3..|.4.|
 
 |...|.5.|6.7|
 
 |---+---+---|
 
 |.3.|7..|...|
 
 |5..|.1.|8..|
 
 |..4|..3|.9.|
 
 |---+---+---|
 
 |..2|4..|...|
 
 |.7.|..9|...|
 
 |8..|.6.|..1|
 
 *-----------* | 	 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Fri Feb 10, 2012 5:56 am    Post subject:  | 
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				I hope my understanding of an X-Chain is correct. If it is, it's my first.
 
 
Multi-coloring; r4c7<>1
 
X-Chain; r9c8<>7 proves r6c7=7; r5c8, r7c7<>7 | 
			 
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		arkietech
 
 
  Joined: 31 Jul 2008 Posts: 1834 Location: Northwest Arkansas USA
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				 Posted: Fri Feb 10, 2012 11:48 am    Post subject:  | 
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				 	  | Marty R. wrote: | 	 		  I hope my understanding of an X-Chain is correct. If it is, it's my first.
 
 
Multi-coloring; r4c7<>1
 
X-Chain; r9c8<>7 proves r6c7=7; r5c8, r7c7<>7 | 	  
 
I don't see or understand x-chain   
 
 
 	  | Code: | 	 		   *-----------------------------------------------------------------------------*
 
 | 1       45689   356789  | 689     479     4678    | 2       358     3589    |
 
 | 279     25689   56789   | 3       279     12678   | 159     4       589     |
 
 | 34      2489    389     | 1289    5       1248    | 6       138     7       |
 
 |-------------------------+-------------------------+-------------------------|
 
 | 29      3       18      | 7       2489    56      | 145     1256    2456    |
 
 | 5       269     679     | 29      1       24      | 8       237     234     |
 
 |a27      18      4       | 56      8-2     3       |x157     9       256     |
 
 |-------------------------+-------------------------+-------------------------|
 
 | 36      15      2       | 4      b37      18      |x3579    5678    5689    |
 
 | 346     7       15      | 18     c23      9       | 345     2568    24568   |
 
 | 8       49      39      | 25      6       257     | 34      27      1       |
 
 *-----------------------------------------------------------------------------*
 
an 273 xy-wing with extension cord.
 
(2=7)r6c1-(7)r6c7=(7)r7c7-(7=3)r7c5-(3=2) => r6c5<>2 | 	 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Fri Feb 10, 2012 1:49 pm    Post subject:  | 
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				Dan,
 
 
I don't understand the extension cord thing.
 
 
Multi-coloring sets r4c7<>1, exposing a 345 triple in c7. I had a third number in r9c8 so I used the X-Chain. Using your grid, it would have been an AIC. The 2 in r9c8 proves 7 in r6c7; r7c7<>7. | 
			 
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		tlanglet
 
 
  Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
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				 Posted: Fri Feb 10, 2012 3:30 pm    Post subject:  | 
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				Flightless w-wing 27 SL (7)r5c38: (2=7)r6c1-r5c3=r5c8-(7=2)r9c8-r9c46=r8c5; r6c5<>2
 
 
Ted | 
			 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Fri Feb 10, 2012 4:39 pm    Post subject:  | 
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				Nice find Ted.    | 
			 
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		Luke451
 
 
  Joined: 20 Apr 2008 Posts: 310 Location: Southern Northern California
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				 Posted: Fri Feb 10, 2012 4:57 pm    Post subject:  | 
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				 	  | Marty R. wrote: | 	 		  | Multi-coloring sets r4c7<>1, exposing a 345 triple in c7. I had a third number in r9c8 so I used the X-Chain. Using your grid, it would have been an AIC. The 2 in r9c8 proves 7 in r6c7; r7c7<>7. | 	  
 
Marty, after your step one I have your position as below:
 
  	  | Code: | 	 		   *-----------------------------------------------------------------------------*
 
 | 1       45689   356789  | 689     479     4678    | 2       358     3589    |
 
 | 279     25689   56789   | 3       279     12678   | 19      4       589     |
 
 | 34      2489    389     | 1289    5       1248    | 6       138     7       |
 
 |-------------------------+-------------------------+-------------------------|
 
 | 29      3       18      | 7       2489    56      | 45      1256    2456    |
 
 | 5       269     679     | 29      1       24      | 8       237     234     |
 
 | 27      18      4       | 56      28      3       | 17      9       56      |
 
 |-------------------------+-------------------------+-------------------------|
 
 | 36      15      2       | 4       37      18      | 79      5678    5689    |
 
 | 346     7       15      | 18      23      9       | 345     2568    24568   |
 
 | 8       49      39      | 25      6       257     | 34      27      1       |
 
 *-----------------------------------------------------------------------------* | 	  
 
I can't find an x-chain/x-cycle at this point. With the x-chain being a single digit
 
technique, it's not clear how (2)r9c8 gets into the picture. | 
			 
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		JC Van Hay
 
 
  Joined: 13 Jun 2010 Posts: 494 Location: Charleroi, Belgium
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				 Posted: Fri Feb 10, 2012 6:07 pm    Post subject:  | 
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				1. Dan's move may be interpreted as a pseudo W Wing : pseudo-cell(2=7)r78c5-7r7c7=7r6c7-(7=2)r6c1 => -2r6c5.
 
2. Even if they aren't usefull in this puzzle, there are 3 easily detected swordfishes : 1C248, 7C157, 9R359.
 
3. The complementary fishes are respectively 2 swordfishes on the rows (1R267 and 7R159) and 1 jellyfish on the columns (9C1579).
 
 
JC | 
			 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Fri Feb 10, 2012 6:32 pm    Post subject:  | 
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				Luke, I'm having a technical problem trying to quote your post, so here's my response without it.
 
 
I had a third number in r9c8 so I used the X-Chain. Using your grid, it would be an AIC. R9c8=2-->r8c5=2-->r6c5=8-->r6c2=1-->r6c7=7. Now we have pincers on 7 at r9c8 and r6c7. I call it an AIC because the trivalue cell at r9c6, by definition, precludes it from being an XY-Chain. | 
			 
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		ronk
 
 
  Joined: 07 May 2006 Posts: 398
 
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				 Posted: Fri Feb 10, 2012 9:06 pm    Post subject:  | 
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				 	  | Marty R. wrote: | 	 		  I hope my understanding of an X-Chain is correct. If it is, it's my first.
 
...
 
X-Chain; r9c8<>7 proves r6c7=7; r5c8, r7c7<>7 | 	  
 
I was also unable to find an x-chain for these eliminations. Please post your pencilmarks at this point. | 
			 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Fri Feb 10, 2012 10:40 pm    Post subject:  | 
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				 	  | ronk wrote: | 	 		   	  | Marty R. wrote: | 	 		  I hope my understanding of an X-Chain is correct. If it is, it's my first.
 
...
 
X-Chain; r9c8<>7 proves r6c7=7; r5c8, r7c7<>7 | 	  
 
I was also unable to find an x-chain for these eliminations. Please post your pencilmarks at this point. | 	  
 
Could you tell me if my understanding of an X-Chain is anywhere near correct? I have inferred from reading previous threads that it's a negative proving a positive, e.g., if cell A is not "X", then cell "B" must "X." | 
			 
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		ronk
 
 
  Joined: 07 May 2006 Posts: 398
 
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				 Posted: Sat Feb 11, 2012 12:10 am    Post subject:  | 
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				 	  | Marty R. wrote: | 	 		  | Could you tell me if my understanding of an X-Chain is anywhere near correct? I have inferred from reading previous threads that it's a negative proving a positive, e.g., if cell A is not "X", then cell "B" must "X." | 	  
 
So far so good. | 
			 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Sat Feb 11, 2012 1:10 am    Post subject:  | 
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				Thank you. Below is the solution I used, which I think is an AIC, whereby the 2 in A proves a 7 in F. When I first posted about using an X-Chain I had 257 in A, so I used the logic that A<>7 proved 7 in F.
 
 
 
 	  | Code: | 	 		  +-------------------+--------------------+-------------------+
 
| 1    45689 356789 |  689   479   4678  |  2    358   3589  |
 
| 279  25689 56789  |  3     279   12678 |  19   4     589   |
 
| 34   2489  389    |  1289  5     1248  |  6    138   7     |
 
+-------------------+--------------------+-------------------+
 
| 29   3     18     |  7     2489  56    |  45   1256  2456  |
 
| 5    269   679    |  29    1     24    |  8    23-7  234   |
 
| 27  E18    4      |  56   D28    3     | F17   9     256   |
 
+-------------------+--------------------+-------------------+
 
| 36   15    2      |  4     37    18    | -79   5678  5689  |
 
| 346  7     15     |  18   C23    9     |  345  2568  24568 |
 
| 8    49    39     | B25    6    B257   |  34  A27    1     |
 
+-------------------+--------------------+-------------------+ | 	 
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		ronk
 
 
  Joined: 07 May 2006 Posts: 398
 
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				 Posted: Sat Feb 11, 2012 3:39 am    Post subject:  | 
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				Marty R, it never occurred to me that you might be trying to use more than one digit in your "x-chain." An x-chain on digit 7, if there were one, would be based on only the pencilmarks for digit 7. IOW you'd be considering only this:
 
 	  | Code: | 	 		  
 
 .  .  7 |  .  7  7 |  .  .  .
 
 7  .  7 |  .  7  7 |  .  .  .
 
 .  .  . |  .  .  . |  .  .  7
 
---------+----------+----------
 
 .  .  . |  7  .  . |  .  .  .
 
 .  .  7 |  .  .  . |  7  .
 
 7  .  . |  .  .  . |  7  .  .
 
---------+----------+----------
 
 .  .  . |  .  7  . |  7  7  .
 
 .  7  . |  .  .  . |  .  .  .
 
 .  .  . |  .  .  7 |  .  7  . | 	  [edit: correct illustration]
  Last edited by ronk on Sat Feb 11, 2012 5:42 am; edited 1 time in total | 
			 
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		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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				 Posted: Sat Feb 11, 2012 4:46 am    Post subject:  | 
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				OK, so if the X-Chain only considers PMs with the particular number that's involved, wouldn't that be some sort of coloring?
 
 
Also, what would you call what I thought was an X-Chain, where you start with the negative to prove the positive? | 
			 
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		ronk
 
 
  Joined: 07 May 2006 Posts: 398
 
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				 Posted: Sat Feb 11, 2012 4:20 pm    Post subject:  | 
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				 	  | Marty R. wrote: | 	 		  | OK, so if the X-Chain only considers PMs with the particular number that's involved, wouldn't that be some sort of coloring? | 	  
 
Of course, it's either the results of simple-coloring or multi-coloring expressed as a chain. Here "multi-" refers to the use of two or more conjugate chains.
 
 
 	  | Marty R. wrote: | 	 		  | Also, what would you call what I thought was an X-Chain, where you start with the negative to prove the positive? | 	  
 
Every useful chain has your "negative-to-positive" property, and it doesn't have to start and end with the same candidate value. These chains may all be expressed as AICs. | 
			 
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		Luke451
 
 
  Joined: 20 Apr 2008 Posts: 310 Location: Southern Northern California
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				 Posted: Sat Feb 11, 2012 8:37 pm    Post subject:  | 
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				 	  | JC Van Hay wrote: | 	 		  | 1. Dan's move may be interpreted as a pseudo W Wing : pseudo-cell(2=7)r78c5-7r7c7=7r6c7-(7=2)r6c1 => -2r6c5. | 	  
 
  	  | Code: | 	 		   *-----------------------------------------------------------------------------*
 
 | 1       45689   356789  | 689     479     4678    | 2       358     3589    |
 
 | 279     25689   56789   | 3       279     12678   | 159     4       589     |
 
 | 34      2489    389     | 1289    5       1248    | 6       138     7       |
 
 |-------------------------+-------------------------+-------------------------|
 
 | 29      3       18      | 7       2489    56      | 145     1256    2456    |
 
 | 5       269     679     | 29      1       24      | 8       237     234     |
 
 | 27      18      4       | 56      28      3       | 157     9       256     |
 
 |-------------------------+-------------------------+-------------------------|
 
 | 36      15      2       | 4       37      18      | 3579    5678    5689    |
 
 | 346     7       15      | 18      23      9       | 345     2568    24568   |
 
 | 8       49      39      | 25      6       257     | 34      27      1       |
 
 *-----------------------------------------------------------------------------* | 	  
 
Thanks for pointing that out, it made me wonder about something that could be exploited.
 
 
Could any (2=7) can act as a w-wing pseudo-cell as long as it meets the necessary endpoint
 
criteria? The two values don't need to be in the same box as above, or even the same house for that matter.
 
 
Just as an example, it seems (2)r8c5 and (7)r9c8 could also be considered a pseudo-cell, as the values are strongly linked. | 
			 
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		arkietech
 
 
  Joined: 31 Jul 2008 Posts: 1834 Location: Northwest Arkansas USA
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				 Posted: Sat Feb 11, 2012 9:36 pm    Post subject:  | 
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				 	  | JC Van Hay wrote: | 	 		  | 1. Dan's move may be interpreted as a pseudo W Wing : pseudo-cell(2=7)r78c5-7r7c7=7r6c7-(7=2)r6c1 => -2r6c5. | 	  
 
 
First what I see as the extension cord.   
 
 
Then a corresponding view of the w-wing.
 
 
(Did I get the Eureka right?)
 
 
Why are not both correct?
 
 
 	  | Code: | 	 		   *-----------------------------------------------------------------------------* 
 
 | 1       45689   356789  | 689     479     4678    | 2       358     3589    | 
 
 | 279     25689   56789   | 3       279     12678   | 159     4       589     | 
 
 | 34      2489    389     | 1289    5       1248    | 6       138     7       | 
 
 |-------------------------+-------------------------+-------------------------| 
 
 | 29      3       18      | 7       2489    56      | 145     1256    2456    | 
 
 | 5       269     679     | 29      1       24      | 8       237     234     | 
 
 |a27      18      4       | 56      8-2     3       |x157     9       256     | 
 
 |-------------------------+-------------------------+-------------------------| 
 
 | 36      15      2       | 4      b37      18      |x3579    5678    5689    | 
 
 | 346     7       15      | 18     c23      9       | 345     2568    24568   | 
 
 | 8       49      39      | 25      6       257     | 34      27      1       | 
 
 *-----------------------------------------------------------------------------*
 
A xy-wing is defined as 3-SIS using bivalue(XY), bivalue(YZ), and bivalue(ZX).  
 
  
 
an 273 xy-wing with extension cord. 
 
(2=7)r6c1-    (7)r6c7=(7)r7c7-   (7=3)r7c5-(3=2)r8c5 => r6c5<>2
 
 x y          extension cord      y z       z x
 
 
 
A w-wing is defined as 3-SIS using bivalue(XY), bilocation(Y), and bivalue(YX).
 
 
(2=7)r6c1-(7)r6c7=(7)r7c7- (7=3-3=2)r78c5 => r6c5<>2
 
 x y       y bilocation     y     x pseudo cell | 	 
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