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Jun 24 VH

 
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Clement



Joined: 24 Apr 2006
Posts: 639
Location: Dar es Salaam Tanzania

PostPosted: Thu Jun 23, 2011 10:39 pm    Post subject: Jun 24 VH Reply with quote

XY-Wing 28 25 58 pivoted in r6c2 or r4c1 solve it.
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kuskey



Joined: 10 Dec 2008
Posts: 120
Location: Pembroke, NH

PostPosted: Fri Jun 24, 2011 4:09 am    Post subject: 24 June VH Reply with quote

Also a 258 xy-wing with pivot at r6c2 setting r4c6<>8.
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cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Fri Jun 24, 2011 1:30 pm    Post subject: Reply with quote

My very clever solution was a Type 6 UR for 35.

There are only two 3's in C3 so remove the 3 from R4C7. There are only two 5's in R5 so remove the 5 from R4C7 - leaving a single 2.
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Marty R.



Joined: 12 Feb 2006
Posts: 5063
Location: Rochester, NY, USA

PostPosted: Fri Jun 24, 2011 3:57 pm    Post subject: Reply with quote

cgordon wrote:
My very clever solution was a Type 6 UR for 35.

There are only two 3's in C3 so remove the 3 from R4C7. There are only two 5's in R5 so remove the 5 from R4C7 - leaving a single 2.

Craig,

I must be getting overly picky in my dotage. Technically that's not a Type 6 because neither number is an X-Wing. In my little world I would view that as a type of Hidden UR.

I had that move noted, along with a similar move for the 68 in boxes 36, as alternatives to the Wing.
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cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Fri Jun 24, 2011 4:19 pm    Post subject: Reply with quote

Quote:
Technically that's not a Type 6


Marty: I always thought Type 6 URs had diagonally positioned pairs with only two of the numbers in any row or column. Thus, one can remove that same number from the multi-valued cell in the opposite row or column. I do things by rote - but this solution has always worked for me -and I do believe the poor thing deserves a proper number. Calling it a "type of Hidden UR" seems so vague" and undefined.

Is Type 7 available?
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Marty R.



Joined: 12 Feb 2006
Posts: 5063
Location: Rochester, NY, USA

PostPosted: Fri Jun 24, 2011 7:13 pm    Post subject: Reply with quote

Craig,

Type 6 does have diagonal pairs, but one of the numbers needs to be an X-Wing. Then the two bivalue cells can be solved for the number that forms the X-Wing.

But the eliminations you describe are valid. Ted would probably describe the pattern as an Almost Unique Rectangle or Almost Type 6.

I've never heard of a Type 7 or higher.
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cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Fri Jun 24, 2011 7:39 pm    Post subject: Reply with quote

Marty: Sorry for being pedantic - but if it doesn’t need an xy wing and always works with just strong links – it deserves better than a “Type of Hidden” or an “Almost” Type 6 UR. Evil or Very Mad
.
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Marty R.



Joined: 12 Feb 2006
Posts: 5063
Location: Rochester, NY, USA

PostPosted: Fri Jun 24, 2011 9:20 pm    Post subject: Reply with quote

OK, give it a name. Laughing
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tlanglet



Joined: 17 Oct 2007
Posts: 2461
Location: Northern California Foothills

PostPosted: Fri Jun 24, 2011 9:46 pm    Post subject: Reply with quote

I agree with Marty that the (35)r45c37 pattern is not a Type 6 UR because it doesn't contain an overlaying x-wing for either digit 3 or 5. Thus the "rote rule" for a Type 6 UR doesn't apply. Also note that the Type 6 rule provides a deletion in the two polyvalued cells of the digit with the overlaying x-wing; different digits in the same cell are not valid.

However, some deletions are possible using this pattern. To prevent the "Deadly Pattern" the internal SIS (Strong Inference Set) consists of r4c7=2 and r5c3=7. I did not see a common result by applying these two constraints.

But looking at the external SIS r5c8=3 and r4c6=5 , I found two deletions.

Given r4c6=5, then r5c8=3 forces r5c7=5 which results in r4c7<>5
In eureka notation this could be written as: aur(35)r45c37[(5)r4c6=(3)r5c8]-(3=5)r5c7; r4c7<>5

Also, given r5c8=3, then r4c6=5 forces r4c3=3 which results in r5c3<>3
In eureka notation this could be written as aur(35)r45c37[(3)r5c8=(5)r4c6]-(5=3)r4c3; r5c3<>3

Together, these two deletions solve the puzzle.

Ted
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Clement



Joined: 24 Apr 2006
Posts: 639
Location: Dar es Salaam Tanzania

PostPosted: Fri Jun 24, 2011 10:07 pm    Post subject: Jun 24 VH Reply with quote

cgordon,
In principle it is a Hidden Unique Rectangle. The issue here I think is which type. As for all unique rectangles we are tying to avoid reducing this rectangle to 35 in all four cells.
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keith



Joined: 19 Sep 2005
Posts: 3136
Location: near Detroit, Michigan, USA

PostPosted: Sat Jun 25, 2011 12:56 am    Post subject: Reply with quote

After basics:
Code:
+----------------+----------------+----------------+
| 234  8    1    | 5    46   29   | 2379 36   267  |
| 23   7    6    | 1    8    29   | 239  5    4    |
| 9    25   45   | 7    46   3    | 1    68   268  |
+----------------+----------------+----------------+
| 28   4    35   | 6    7    58   | 235  1    9    |
| 78   1    357  | 9    2    4    | 35   368  68   |
| 6    25   9    | 3    1    58   | 257  4    278  |
+----------------+----------------+----------------+
| 1    6    8    | 2    3    7    | 4    9    5    |
| 5    3    2    | 4    9    6    | 8    7    1    |
| 47   9    47   | 8    5    1    | 6    2    3    |
+----------------+----------------+----------------+
Keith
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cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Sat Jun 25, 2011 3:55 pm    Post subject: Reply with quote

Quote:
OK, give it a name.


My last word- I promise. If it's a Hidden Unique Rectangle call it a HUR
(or BEN).
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