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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Sun Mar 18, 2012 1:30 pm    Post subject: Interesting ... |   |  
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				| This from my Saturday newspaper, labelled "Universal Sudoku Puzzle".  I have not before seen these puzzles require advanced moves. Keith 	  | Code: |  	  | Puzzle: AD20120317 +-------+-------+-------+
 | 9 4 1 | 7 . . | . . 8 |
 | . 2 . | . . 6 | . . 7 |
 | 7 . 6 | 1 . . | . . 3 |
 +-------+-------+-------+
 | . . 7 | . . 5 | . . 4 |
 | . . . | . . . | . . . |
 | 8 . . | 9 . . | 2 . . |
 +-------+-------+-------+
 | 4 . . | . . 9 | 3 . 6 |
 | 3 . . | 5 . . | . 4 . |
 | 6 . . | . . 8 | 7 5 9 |
 +-------+-------+-------+
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		| Auburnmom 
 
 
 Joined: 13 Mar 2008
 Posts: 25
 Location: Auburn, AL
 
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				|  Posted: Sun Mar 18, 2012 2:20 pm    Post subject: |   |  
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				| I also have this puzzle and am stopped.  So I am sure there is a step that is beyond my ability. 
 [/img]
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Sun Mar 18, 2012 4:41 pm    Post subject: |   |  
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				| Given Keith's comments, I did not pursue non-advanced moves but found three views of the same deletions. 
 After basics:
 
  	  | Code: |  	  | *-----------------------------------------------------------------------------* | 9       4       1       | 7       235     23      | 56      26      8       |
 | 5       2       3       | 48      489     6       | 149     19      7       |
 | 7       8       6       | 1       2459    24      | 459     29      3       |
 |-------------------------+-------------------------+-------------------------|
 | 12      369     7       | 368     12      5       | 689     3689    4       |
 | 12      3569    459     | 3468    123478  12347   | 689     36789   15      |
 | 8       356     45      | 9       1347    1347    | 2       367     15      |
 |-------------------------+-------------------------+-------------------------|
 | 4       57      58      | 2       17      9       | 3       18      6       |
 | 3       79      89      | 5       6       17      | 18      4       2       |
 | 6       1       2       | 34      34      8       | 7       5       9       |
 *-----------------------------------------------------------------------------*
 
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 almost xy-wing (24-9)[r3c68+r2c5]=(8)r2c5-(8=4)r2c4-(4=2)r3c6-(2=9)r3c8; r2c78, r3c5<>9
 or
 anp(9=48)r2c54-(4=2)r3c6-(2=9)r3c8; r2c78, r3c5<>9
 or
 ALS XZ; r2c78, r3c5<>9
 a=(489)r2c45
 b=(249)r3c68
 x=4
 z=9
 
 Ted
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		| JC Van Hay 
 
 
 Joined: 13 Jun 2010
 Posts: 494
 Location: Charleroi, Belgium
 
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				|  Posted: Sun Mar 18, 2012 5:01 pm    Post subject: |   |  
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				|  	  | Code: |  	  | After 8 singles 
 +---------------+---------------------+--------------------+
 | 9   4     1   | 7     235     23    | 56      26      8  |
 | 5   2     3   | 48    8-4(9)  6     | -9(14)  -9(1)   7  |
 | 7   8     6   | 1     24(59)  24    | 9(45)   29      3  |
 +---------------+---------------------+--------------------+
 | 12  369   7   | 368   1238    5     | 1689    13689   4  |
 | 12  3569  459 | 3468  123478  12347 | 15689   136789  15 |
 | 8   356   45  | 9     1347    1347  | 2       1367    15 |
 +---------------+---------------------+--------------------+
 | 4   57    58  | 2     17      9     | 3       18      6  |
 | 3   79    89  | 5     6       17    | 18      4       2  |
 | 6   1     2   | 34    34      8     | 7       5       9  |
 +---------------+---------------------+--------------------+
 
 4-SIS AIC : 9r2c5=(9-5)r3c5=(5-4)r3c7=(4-1)r2c7=1r2c8 => -4r2c5, -9r2c78; stte
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sun Mar 18, 2012 5:12 pm    Post subject: |   |  
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				|  	  | Code: |  	  | *-----------------------------------------------------------------------------* | 9       4       1       | 7       235     23      | 56      26      8       |
 | 5       2       3       | 48      489     6       | 149     19      7       |
 | 7       8       6       | 1       2459    24      | 459     29      3       |
 |-------------------------+-------------------------+-------------------------|
 | 12      369     7       | 368     12      5       | 689     3689    4       |
 | 12      3569    459     | 3468    123478  12347   | 689     36789   15      |
 | 8       356     45      | 9       1347    1347    | 2       367     15      |
 |-------------------------+-------------------------+-------------------------|
 | 4       57      58      | 2       17      9       | 3       18      6       |
 | 3       79      89      | 5       6       17      | 18      4       2       |
 | 6       1       2       | 34      34      8       | 7       5       9       |
 *-----------------------------------------------------------------------------*
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 I don't know if mine is similar as JC's due to my Eureka deficiencies. But in a short AIC, r3c8=2 proves r2c5=9; r2c78, r3c5<>9.
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		| JC Van Hay 
 
 
 Joined: 13 Jun 2010
 Posts: 494
 Location: Charleroi, Belgium
 
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				|  Posted: Sun Mar 18, 2012 6:00 pm    Post subject: |   |  
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				| Marty, 
 What was exactly your path ? ...
 
 Furthermore, you only need "r3c8=2 proves r3c5=5" to get r3c5<>9
   
 In Eureka, among a lot of other possibilities as Ted showed :
 
 
 (9=2)r3c8-AHP[2r1c8=23r1c56]-5r1c5=5r3c5 => -9r3c5
Regards, JC.or
 (9=2)r3c8-(2=6)r1c8-(6=5)r1c7-5r1c5=5r3c5 => -9r3c5
 or
 ...
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sun Mar 18, 2012 6:48 pm    Post subject: |   |  
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				| Path: 
 
  	  | Code: |  	  | *----------------------------------------------------------------------------------* | 9       4       1       |  7        235      23      | 56       26      8       |
 | 5       2       3       | C48      D489      6       | 149      19      7       |
 | 7       8       6       |  1        2459    B24      | 459     A29      3       |
 |-------------------------+---------- -----------------+--------------------------|
 | 12      369     7       |  368      12       5       | 689      3689    4       |
 | 12      3569    459     |  3468     123478   12347   | 689      36789   15      |
 | 8       356     45      |  9        1347     1347    | 2        367     15      |
 |-------------------------+----------------------------+--------------------------|
 | 4       57      58      |  2        17       9       | 3        18      6       |
 | 3       79      89      |  5        6        17      | 18       4       2       |
 | 6       1       2       |  34       34       8       | 7        5       9       |
 *---------------------------------------------------------------------------------*
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 I can follow how the 2 proves the 5 but that's probably not the kind of thing I'd notice.
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		| arkietech 
 
 
 Joined: 31 Jul 2008
 Posts: 1834
 Location: Northwest Arkansas USA
 
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				|  Posted: Sun Mar 18, 2012 7:16 pm    Post subject: |   |  
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				| I got the same as Ted   
 
  	  | Code: |  	  | *-----------------------------------------------------------------------------* | 9       4       1       | 7      d235     23      |c56     b26      8       |
 | 5       2       3       | 48      489     6       | 149     19      7       |
 | 7       8       6       | 1      e245-9   24      | 459    a29      3       |
 |-------------------------+-------------------------+-------------------------|
 | 12      369     7       | 368     12      5       | 689     3689    4       |
 | 12      3569    459     | 3468    123478  12347   | 689     36789   15      |
 | 8       356     45      | 9       1347    1347    | 2       367     15      |
 |-------------------------+-------------------------+-------------------------|
 | 4       57      58      | 2       17      9       | 3       18      6       |
 | 3       79      89      | 5       6       17      | 18      4       2       |
 | 6       1       2       | 34      34      8       | 7       5       9       |
 *-----------------------------------------------------------------------------*
 xy-wing with extension???
 (9=2)r3c8-(2=6)r1c8-(6=5)r1c7-(5)r1c5=(5)r3c5 => r1c5<>9
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		| JC Van Hay 
 
 
 Joined: 13 Jun 2010
 Posts: 494
 Location: Charleroi, Belgium
 
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				|  Posted: Sun Mar 18, 2012 7:43 pm    Post subject: |   |  
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				| Marty, 
 OK, now I understand your logic.
 
 In a word, you are using the same SIS as Ted who gave 3 different interpretations of the same deletions.
 
 In Eureka, I am reading your path as
 
 4-SIS t-Chain : (9=2)r3c8-(2=4)r3c6-(4=8)r2c4-(84#2=9)r2c5 => -9r3c5, -9r2c78
 
 That is :
 
 Either r3c8=9; Or r3c8=2, r3c6<>2, r3c6=4, r2c4<>4, r2c4=8, [r2c5<>8 and r2c5<>4(because of r3c6=4)], r2c5=9
 => pincers (9r3c8,9r2c5) => r3c5<>9 and r2c78<>9
 
 Thanks a lot for the clarifications.
 
 Regards, JC
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		| arkietech 
 
 
 Joined: 31 Jul 2008
 Posts: 1834
 Location: Northwest Arkansas USA
 
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				|  Posted: Sun Mar 18, 2012 10:30 pm    Post subject: |   |  
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				| wouldn't 	  | JC Van Hay wrote: |  	  | (9=2)r3c8-(2=4)r3c6-(4=8)r2c4-(84#2=9)r2c5 => -9r3c5, -9r2c78 
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 (9=2)r3c8-(2=4)r3c6-(48=9)r2c45 => -9r3c5, -9r2c78
 
 be better?
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		| JC Van Hay 
 
 
 Joined: 13 Jun 2010
 Posts: 494
 Location: Charleroi, Belgium
 
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				|  Posted: Mon Mar 19, 2012 8:16 pm    Post subject: |   |  
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				| Dan, 
 Of course, it's better to write (9=2)r3c8-(2=4)r3c6-(4=89)r2c45 => -9r3c5, -9r2c78.
 
 However, in my previous post, I hoped to translate Marty's logic as faithfully as possible.
 Therfore, my "detailed" presentation.
 
 Regards, JC.
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