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Collection 5/21/12

 
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Mon May 21, 2012 6:48 am    Post subject: Collection 5/21/12 Reply with quote

Code:

 *-----------*
 |.7.|.8.|4..|
 |.4.|7.2|...|
 |2.5|.3.|..7|
 |---+---+---|
 |..8|...|.1.|
 |..6|.5.|7.8|
 |79.|...|.3.|
 |---+---+---|
 |9..|.65|8..|
 |...|8..|.79|
 |..1|2..|3..|
 *-----------*
 

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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Mon May 21, 2012 12:44 pm    Post subject: Reply with quote

Code after basics:
Code:
*--------------------------------------------------------------------*
 | 16     7      39     | 5      8      169    | 4      269    1236   |
 | 168    4      39     | 7      19     2      | 1569   5689   1356   |
 | 2      168    5      | 1469   3      1469   | 169    689    7      |
 |----------------------+----------------------+----------------------|
 | 345    235    8      | 3469   2479   34679  | 269    1      246    |
 | 134    123    6      | 349    5      349    | 7      249    8      |
 | 7      9      24     | 146    124    8      | 256    3      2456   |
 |----------------------+----------------------+----------------------|
 | 9      23     7      | 134    6      5      | 8      24     124    |
 | 3456   2356   24     | 8      14     134    | 1256   7      9      |
 | 4568   568    1      | 2      79     79     | 3      456    456    |
 *--------------------------------------------------------------------*

axy-wing(24-3)r8c3+r7c2/r8c6=(1)r8c6-(1=4=2)r8c53-(2=3)r7c2; r7c4,r8c12<>3

Ted
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Mon May 21, 2012 1:09 pm    Post subject: Reply with quote

tlanglet wrote:

axy-wing(24-3)r8c3+r7c2/r8c6=(1)r8c6-(1=4=2)r8c53-(2=3)r7c2; r7c4,r8c12<>3

Nice find Ted. Very Happy

also there is a nice w-wing hiding.

Code:
 *--------------------------------------------------------------------*
 | 16     7      39     | 5      8      169    | 4      269    1236   |
 | 168    4      39     | 7      19     2      | 1569   5689   1356   |
 | 2      168    5      | 1469   3      1469   | 169    689    7      |
 |----------------------+----------------------+----------------------|
 | 345    235    8      | 3469   2479   34679  | 269    1      246    |
 | 134    123    6      | 349    5      349    | 7      249    8      |
 | 7      9      24     | 146    124    8      | 256    3      2456   |
 |----------------------+----------------------+----------------------|
 | 9      3-2    7      |#134    6      5      | 8     *24     124    |
 | 3456   2356  *24     | 8     #14    #134    | 156-2  7      9      |
 | 4568   568    1      | 2      79     79     | 3      456    456    |
 *--------------------------------------------------------------------*
w-wing
(2=4)r7c8-r7c4=r8c56-(4=2)r8c3 => r7c2,r8c7<>2


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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Mon May 21, 2012 1:30 pm    Post subject: Reply with quote

A second "similar" w-wing also exits but it needs a pincer transport.

(4=2)r7c3-r5c2=r5c8-(2=4)r7c8-r9c89=r9c1; r45c1,r8c3<>4

I normally approach a puzzle in a given sequence of steps and simply use the first solution that I find. In this case, I never got around to looking for w-wings since I was looking for xy-wings first, including almost xy-wings. That is also why I recently missed two xyz-wing solutions since I never check for them early in my sequence.

Ted
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Mon May 21, 2012 1:53 pm    Post subject: Reply with quote

I wonder if anyone has studied whether xy-wings or w-wings solve the most puzzles. To me a w-wing is much easier to spot (this one being an exception).
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keith



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

PostPosted: Mon May 21, 2012 4:37 pm    Post subject: Reply with quote

arkietech wrote:
I wonder if anyone has studied whether xy-wings or w-wings solve the most puzzles. To me a w-wing is much easier to spot (this one being an exception).

I think that is an unknowable question (or answer?). The reason is that puzzles are screened based on the techniques needed to solve them. I imagine that some sites sort puzzles so that, at some level, XY-wings will not solve them. I doubt they screen for W- or M-wings.

Keith
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Marty R.



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

PostPosted: Mon May 21, 2012 4:45 pm    Post subject: Reply with quote

Quote:
w-wing
(2=4)r7c8-r7c4=r8c56-(4=2)r8c3 => r7c2,r8c7<>2


Dan, it looks like you're saying that the W-Wing solves the puzzle. I missed that because after the W-Wing I needed the X-Wing on 2 in r17.

This is where the W-Wing takes me:
Code:

+-------------+----------------+----------------+
| 16   7   39 | 5    8    169  | 4    269  1236 |
| 168  4   39 | 7    19   2    | 1569 5689 1356 |
| 2    168 5  | 1469 3    1469 | 169  689  7    |
+-------------+----------------+----------------+
| 345  25  8  | 3469 2479 4679 | 269  1    246  |
| 134  12  6  | 349  5    49   | 7    249  8    |
| 7    9   24 | 146  124  8    | 256  3    2456 |
+-------------+----------------+----------------+
| 9    3   7  | 14   6    5    | 8    24   124  |
| 456  256 24 | 8    14   3    | 156  7    9    |
| 4568 568 1  | 2    79   79   | 3    456  456  |
+-------------+----------------+----------------+

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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Mon May 21, 2012 5:04 pm    Post subject: Reply with quote

Marty R wrote:
Dan, it looks like you're saying that the W-Wing solves the puzzle. I missed that because after the W-Wing I needed the X-Wing on 2 in r17.


Check the 1's in col 6.

I should have indicated lclste. Embarassed
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Clement



Joined: 24 Apr 2006
Posts: 1111
Location: Dar es Salaam Tanzania

PostPosted: Mon May 21, 2012 6:25 pm    Post subject: Collection 5/21/12 Reply with quote

We can eliminate 3 in r7c4 using the numbers left in r7c8 the 2 and 4 (Digit Forcing Chains) as follows:-
If r7c8=2 => r7c2=3; r7c4<>3.
If r7c8=4 => r9c89<>4, r8c3=2 => r7c2=3; r7c4<>3 solves it.
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Marty R.



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

PostPosted: Mon May 21, 2012 7:20 pm    Post subject: Reply with quote

Quote:
Check the 1's in col 6.


Up to my old tricks. Embarassed
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