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Free Press October 16, 2009

 
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA
PostPosted: Fri Oct 16, 2009 7:26 pm    Post subject: Free Press October 16, 2009 Reply with quote
Code:
Puzzle: FP101609
+-------+-------+-------+
| . . 1 | 3 . . | . . 4 |
| . 3 . | . 2 . | . . . |
| . . . | . . . | 5 . . |
+-------+-------+-------+
| 4 . . | . 8 5 | . 6 9 |
| . . . | . . . | 1 . . |
| . 1 . | 9 3 . | . . 2 |
+-------+-------+-------+
| . . 6 | . . . | . 8 . |
| . 8 . | . 6 . | . 5 . |
| 9 . . | . . 7 | 3 . . |
+-------+-------+-------+

Enjoy!

Keith
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA
PostPosted: Fri Oct 16, 2009 9:45 pm    Post subject: Reply with quote
A hang on-- here we go -- type of xy-chain does it
Code:
 *-----------------------------------------------------------*
 | 68    56    1     | 3     579   89    | 2     79    4     |
 | 57    3     49    | 57    2     149   | 6     19    8     |
 | 2     49    78    | 6     479   1489  | 5     179   3     |
 |-------------------+-------------------+-------------------|
 | 4     2     3     | 1     8     5     | 7     6     9     |
 | 68    69    89    | 27    47    24    | 1     3     5     |
 | 57    1     57    | 9     3     6     | 8     4     2     |
 |-------------------+-------------------+-------------------|
 | 3     7     6     | 25    59    29    | 4     8     1     |
 | 1     8     2     | 4     6     3     | 9     5     7     |
 | 9     45    45    | 8     1     7     | 3     2     6     |
 *-----------------------------------------------------------*
XY-Chain:
(4=2)r5c6-(2=7)r5c4-(7=5)r2c4-(5=7)r2c1-(7=5)r6c1-(5=7)r6c3-(7=8)r3c3-(8=9)r5c3-(9=4)r2c3
=> r2c6<>4 singles remain
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Fri Oct 16, 2009 9:54 pm    Post subject: Reply with quote
I had two steps:

Quote:
A xy-wing 68-9 with extended pincer. Vertex 68 in r1c1, pincer 89 in r1c6 and pincer 69: (6)r1c1 - (6=8)r5c1 - (8=9)r5c3 -(9)r2c3 = (9)r3c2; r3c56<>9
BUG+1 sets r3c6=4
Ted
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA
PostPosted: Fri Oct 16, 2009 11:27 pm    Post subject: Reply with quote
After basics:

Code:
+----------------+----------------+----------------+
| 68#  56   1    | 3    579  89@  | 2    79   4    |
| 57   3    49%  | 57   2    149  | 6    19   8    |
| 2    49%  78   | 6   47-9 148-9 | 5    179  3    |
+----------------+----------------+----------------+
| 4    2    3    | 1    8    5    | 7    6    9    |
| 68#  69   89@  | 27   47   24   | 1    3    5    |
| 57   1    57   | 9    3    6    | 8    4    2    |
+----------------+----------------+----------------+
| 3    7    6    | 25   59   29   | 4    8    1    |
| 1    8    2    | 4    6    3    | 9    5    7    |
| 9    45   45   | 8    1    7    | 3    2    6    |
+----------------+----------------+----------------+

The 89 pair @ are a W-wing with link #. Coloring % removes two candidates 9 as shown.

This reduces it to a BUG+1.

Keith
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daj95376



Joined: 23 Aug 2008
Posts: 3854
PostPosted: Sat Oct 17, 2009 2:58 am    Post subject: Reply with quote
Code:
 after basics ... a UR using SLs on <7> and <9>
 *-----------------------------------------------------------*
 | 68    56    1     | 3    *79+5  89    | 2    *79    4     | <         SL on <7> and
 | 57    3     49    | 57    2     149   | 6     19    8     |   grouped SL on <9>
 | 2     49    78    | 6    *79+4  1489  | 5    *79+1  3     |
 |-------------------+-------------------+-------------------|
 | 4     2     3     | 1     8     5     | 7     6     9     |
 | 68    69    89    | 27    47    24    | 1     3     5     |
 | 57    1     57    | 9     3     6     | 8     4     2     |
 |-------------------+-------------------+-------------------|
 | 3     7     6     | 25    59    29    | 4     8     1     |
 | 1     8     2     | 4     6     3     | 9     5     7     |
 | 9     45    45    | 8     1     7     | 3     2     6     |
 *-----------------------------------------------------------*
                                                 ^                       SL on <7>

 r13c58  <79> UR via s-link              <> 9    r3c5

(basics)

         BUG+1                           =  4    r3c6
______________________________________________________________________________________

How on the UR?

Code:
                                 (7)r1c5
(9)r3c5 - (9)r1c56 = (9-7)r1c8 =         => r13c58 = 7-9-7-9 DP; => r3c5 <> 9
                                 (7)r3c8
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Sat Oct 17, 2009 3:17 am    Post subject: Reply with quote
Keith, your w-wing with coloring is identical to my xy-wing with extended pincer. How interesting that we used the same cells but for different patterns.

Ted
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