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Oct 12 VH

 
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roaa



Joined: 18 Apr 2009
Posts: 112
Location: Sweden

PostPosted: Mon Oct 12, 2009 8:49 am    Post subject: Oct 12 VH Reply with quote

XY-wing 567 solved it
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Tue Oct 13, 2009 11:47 pm    Post subject: Reply with quote

if you use the draw/play page, and just do a sweep without making any moves or placing any singles,
the non-puzzle breaking xyz-wing is available from the start.

its not til the cascading singles and naked pairs start to fizzle out that the puzzle breaking xy-wing is available.
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Jeff



Joined: 06 May 2007
Posts: 46

PostPosted: Sat Oct 17, 2009 3:50 am    Post subject: Reply with quote

I am really stumped on this one. I found the xy 567, but I can't seem to solve the puzzle. Maybe, I have an error somewhere. Could someone tell me where I went wrong. Many thanks,


Code:

+----------------+-------------+-----------+
| 15    15   3   | 2   7   9   | 8 46  46  |
| 2     7    4   | 6   8   3   | 1 9   5   |
| 8     9    6   | 5   4   1   | 7 3   2   |
+----------------+-------------+-----------+
| 3479  34   8   | 379 2   6   | 5 1   47  |
| 6     14   157 | 8   15  457 | 9 2   3   |
| 13479 2    157 | 379 135 457 | 6 478 478 |
+----------------+-------------+-----------+
| 357   8    2   | 1   356 57  | 4 67  9   |
| 347   1346 17  | 37  9   8   | 2 5   167 |
| 157   156  9   | 4   56  2   | 3 78  178 |
+----------------+-------------+-----------+
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

PostPosted: Sat Oct 17, 2009 3:59 am    Post subject: Reply with quote

Jeff,

I have no way of knowing where you went wrong, but you might want to take another look. Your XY-Wing does finish the puzzle. If you look again and get stuck, just post the position you're stuck at and someone will be along to help.

Good luck.
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Jeff



Joined: 06 May 2007
Posts: 46

PostPosted: Sat Oct 17, 2009 4:13 am    Post subject: Reply with quote

I implemented the xy-wing 567 and after doing this, I have the configuration that is shown above in my initial note. I just can't find another step to take to solve the puzzle. I have checked all my numbers (pencil notes) and they all seem to be correct (see diagram above). I would appreciate any suggestions out there. Many thanks,
Jeff
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

PostPosted: Sat Oct 17, 2009 4:21 am    Post subject: Reply with quote

Jeff,

Maybe you overlooked the fact that the pincers in r7c8 and r9c5 take out the 6 from r7c5.
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Sat Oct 17, 2009 4:22 am    Post subject: Reply with quote

This is what was posted:
Code:
+-------------------+-------------------+-------------------+
| 15    15    3     | 2     7     9     | 8     46    46    |
| 2     7     4     | 6     8     3     | 1     9     5     |
| 8     9     6     | 5     4     1     | 7     3     2     |
+-------------------+-------------------+-------------------+
| 3479  34    8     | 379   2     6     | 5     1     47    |
| 6     14    157   | 8     15    457   | 9     2     3     |
| 13479 2     157   | 379   135   457   | 6     478   478   |
+-------------------+-------------------+-------------------+
| 357   8     2     | 1     35-6  57@   | 4     67@   9     |
| 347   1346  17    | 37    9     8     | 2     5     167   |
| 157   156   9     | 4     56@  2     | 3     78    178   |
+-------------------+-------------------+-------------------+

I have highlighted the XY-wing which, after a few more singles, solves the puzzle.

Keith


Last edited by keith on Sat Oct 17, 2009 4:33 am; edited 1 time in total
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wapati



Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.

PostPosted: Sat Oct 17, 2009 4:29 am    Post subject: Reply with quote

I can't see how the 1 vanished from r8c1. A puzzlement!
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Jeff



Joined: 06 May 2007
Posts: 46

PostPosted: Sat Oct 17, 2009 4:36 pm    Post subject: Reply with quote

I thank Marty R. for pointing out that I had missed the extra 6 that can be removed in the 567 xy-wing. That did it.

In answer to Wapati's question about the missing 1, there is a xyz-wing made up of the 1,5 in R1C1, the 1,5,7 in R9C1, and the 1,7 in R8C3. This removes the 1 in R8C1.
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wapati



Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.

PostPosted: Sat Oct 17, 2009 10:51 pm    Post subject: Reply with quote

Jeff wrote:

In answer to Wapati's question about the missing 1, there is a xyz-wing made up of the 1,5 in R1C1, the 1,5,7 in R9C1, and the 1,7 in R8C3. This removes the 1 in R8C1.


Nope, you do need to re-think that.
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