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Is a finned x-wing like a Kraken x-wing?

 
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Mon Mar 16, 2009 3:22 pm    Post subject: Is a finned x-wing like a Kraken x-wing? Reply with quote
I was working Danny,s puzzle "T_01 Puzzle 17" and found this situation.

After an initial x-wing on<3>, I had the following code:
Code:


 *--------------------------------------------------------------------*
 | 5      3      9      | 8      6      1      | 2      47     47     |
 | 8      6      2      | 4      3      7      | 1      59     59     |
 | 1      4      7      | 2      5      9      | 3      6      8      |
 |----------------------+----------------------+----------------------|
 | 29     289    38     | 7      18     6      | 459    1459   13459  |
 | 6      789    5      | 3      18     4      | 79     2      179    |
 | 37     1      4      | 5      9      2      | 8      37     6      |
 |----------------------+----------------------+----------------------|
 | 479    5      13     | 19     2      8      | 6      1479   13479  |
 | 279    2789   18     | 6      4      3      | 579    15789  1579   |
 | 349    89     6      | 19     7      5      | 49     13489  2      |
 *--------------------------------------------------------------------*

I missed the obvious x-wing7 in r58c27, but saw the finned x-wing7 in r67c18 with the fin in r7c9. This finned x-wing deletes <7> from r8c8.

However, if the finned cell is treated like a "Kraken x-wing" then more deletiion are possible. The other possible deletions of the x-wing are in r1c8 and r8c1. So, if the fin is true: (7)r7c9 - (7)r1c9 = (7)r1c8 - (7)r6c8 = (7)r6c1 - r8c1. Thus r8c1<>7.

I do not see any problem with treating a finned condition like a Kraken situation. I would appreciate comments by all.

Ted
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daj95376



Joined: 23 Aug 2008
Posts: 3854
PostPosted: Tue Mar 17, 2009 11:44 am    Post subject: Reply with quote
To me, a Kraken fish contains at least one fin cell that doesn't see at least one cell where it causes an elimination. That's what you are doing.

It's a good idea to explain how any Kraken fin cell(s) result in an elimination. Your single-digit chain above is fine ... and can have its notation shortened ... and include the finned elimination as well.

Code:
(7) r7c9 - r1c9 = r1c8 - r6c8 = r6c1 - r8c1 => r8c18<>7
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wapati



Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.
PostPosted: Tue Mar 17, 2009 12:13 pm    Post subject: Re: Is a finned x-wing like a Kraken x-wing? Reply with quote
tlanglet wrote:

I do not see any problem with treating a finned condition like a Kraken situation. I would appreciate comments by all.
Ted

I'd add r1c89 and have a swordfish with all your eliminations and r8c9 too! Smile
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