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Not Quite Multidigit X-Wing (Extended) Example

 
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Bud



Joined: 06 May 2010
Posts: 47
Location: Tampa, Florida
PostPosted: Sat Feb 26, 2011 5:34 pm    Post subject: Not Quite Multidigit X-Wing (Extended) Example Reply with quote
I have found several examples of this technique and not all of them are extended. A multidigit X-Wing consist of 4 cells with 4 conjugate digits. This basic technique uses 4 cells with 3 conjugate digits. I did not call this almost, because I did not use almost techniques to analyze it. If anyone wants to see other examples, I can add some to this post.

054030090000000400200604005005000070000971000010000800400308007538000000090450038

The diagram below shows the puzzle after all basic moves are made.
The cells marked with * in rows2 and 8 is the basic pattern and r6c4 makes this an extended pattern. In the basic pattern row 2 contains a 5 conjugate, row 8 contains a 7 conjugate, and column 6 contains a 9 conjugate. If r2c6=9, r2c4=5 and r2c6=2. If r8c6=9, r8c4=7. This implies that r2c4<>7 and r8c4<>2.
Code:

+--------------------+-------------------+---------------------+
| 168    5     4     | 1278   3     27   | 1267   9     126    |
| 13689  678   1369  |125-78* 1289  2579*| 4      1268  1236   |
| 2      78    139   | 6      189   4    | 137    18    5      |
+--------------------+-------------------+---------------------+
| 369    246   5     | 28     2468  236  | 12369  7     123469 |
| 368    2468  236   | 9      7     1    | 2356   2456  2346   |
| 3679   1     23679 | 25*    246   2356 | 8      246   23469  |
+--------------------+-------------------+---------------------+
| 4      26    126   | 3      1269  8    | 12569  1256  7      |
| 5      3     8     | 1-27*  1269  2679*| 1269   1246  12469  |
| 167    9     1267  | 4      5     26   | 126    3     8      |
+--------------------+-------------------+---------------------+
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daj95376



Joined: 23 Aug 2008
Posts: 3854
PostPosted: Sat Feb 26, 2011 7:33 pm    Post subject: Reply with quote
Also, a chain contains a sub-chain with an alternate elimination.

Code:
 (2=5)r6c4 - (5)r2c4 = (5-9)r2c6 = (9-7)r8c6 = (7)r8c4  =>  r8c4<>2
             .........................................  =>  r2c4<>7
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