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Puzzle 10/09/05: A

 
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daj95376



Joined: 23 Aug 2008
Posts: 3854
PostPosted: Sun Sep 05, 2010 1:01 am    Post subject: Puzzle 10/09/05: A Reply with quote
Code:
 +-----------------------+
 | . . 4 | 7 5 1 | . . . |
 | . . . | . . . | . . . |
 | 7 . 3 | . 4 9 | 1 . . |
 |-------+-------+-------|
 | 4 . . | . 2 . | 5 . . |
 | 5 . 7 | 6 1 3 | . . 4 |
 | 8 . 1 | . 7 5 | 3 . . |
 |-------+-------+-------|
 | . . 5 | 1 . 7 | . 8 . |
 | . . . | . . . | 9 1 . |
 | . . . | . 9 . | . . 5 |
 +-----------------------+

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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium
PostPosted: Sun Sep 05, 2010 11:01 am    Post subject: Reply with quote
A two steps solution :
Quote:
Type 1 UR (29)R56C28 : r6c8<>29=6
XY Wing (-256), pivot at R3C2 : => r1c7<>2
Or a one step proof :
Quote:
Colouring the bivalues in B1 leads to r2c9<>28. Interpretation :
7-SIS AIC written as a 4-SIS ALS Chain : [(28)R3C9 (26)R1C7] [(62)R1C1 (12)R2C1] [1R9 7R9] 7C9 : "ANP(28=6) ANP(6=12) AHP(1=17) 7C9" : NP(28)r3c9,r1c7=(7)r2c9 : => r2c9<>28=7
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peterj



Joined: 26 Mar 2010
Posts: 974
Location: London, UK
PostPosted: Sun Sep 05, 2010 2:57 pm    Post subject: Reply with quote
Same as JC

JC, I am struggling a bit to see all the ALS in your solution, but it did lead me to what I assume is a similar AIC using 3 hub cells...
Quote:
(7)r9c7=(7-1)r9c2=(1-5)r2c2=(5-4)r2c8=r2c7 ; r2c7<>7
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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium
PostPosted: Sun Sep 05, 2010 4:54 pm    Post subject: Reply with quote
Peter, marvelous interpretation Exclamation I understand your confusion : I overlooked I already eliminated (6)r3c9 by colouring Embarassed . Furthermore, I stopped colouring too early to see your simpler step ! Congratulations Very Happy Thank you for the checking.
Regards,
JC
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Mon Sep 06, 2010 12:41 am    Post subject: Reply with quote
Same as JC.
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