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Vanhegan extreme September 25, 2012

 
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arkietech



Joined: 31 Jul 2008
Posts: 1687
Location: Northwest Arkansas USA

PostPosted: Tue Sep 25, 2012 5:32 am    Post subject: Vanhegan extreme September 25, 2012 Reply with quote

Code:

 *-----------*
 |6..|5.7|..3|
 |...|.3.|...|
 |4.1|...|8.5|
 |---+---+---|
 |.4.|.7.|.1.|
 |..2|6.4|5..|
 |.7.|.5.|.9.|
 |---+---+---|
 |7.3|...|2.1|
 |...|.6.|...|
 |5..|1.3|..6|
 *-----------*
 


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Clement



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

PostPosted: Tue Sep 25, 2012 12:06 pm    Post subject: Vanhagen Extreme September 25, 2012 Reply with quote

Code:

+--------------+--------------+--------------+
| 6    89  89  | 5    14  7   | 14  2    3   |
| 2    5   7   | 48   3   189 | 149 6    49  |
| 4    3   1   | 29   29  6   | 8   7    5   |
+--------------+--------------+--------------+
| 389  4   5   | 2389 7   289 | 6   1    28  |
| 1389 18  2   | 6    189 4   | 5   38   7   |
| 138  7   6   | 238  5   128 | 34  9    248 |
+--------------+--------------+--------------+
| 7    6   3   | 489  489 589 | 2   458  1   |
| 18   128 48  | 7    6   258 | 39  3458 89  |
| 5    289 489 | 1    248 3   | 7   48   6   |
+--------------+--------------+--------------+
UR 89 in Grid r19c23; r9c23<>8 solves it.
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tlanglet



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

PostPosted: Tue Sep 25, 2012 4:16 pm    Post subject: Reply with quote

The Type 4 UR(89) is an obvious solution but I enjoyed an almost AIC.

AAIC: {(4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7} = (9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7

Ted
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Marty R.



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

PostPosted: Tue Sep 25, 2012 5:07 pm    Post subject: Reply with quote

I also used the obvious UR.
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arkietech



Joined: 31 Jul 2008
Posts: 1687
Location: Northwest Arkansas USA

PostPosted: Tue Sep 25, 2012 5:57 pm    Post subject: Reply with quote

tlanglet wrote:
The Type 4 UR(89) is an obvious solution but I enjoyed an almost AIC.

AAIC: {(4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7} = (9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7

Ted


Ted I am lost in your notation. Confused (1=8)r5c5 What happened to the 9

removing the 9 will solve the puzzle. Very Happy

(9=2)r3c5-r9c5=(2-5)r8c6=(5-9)r7c6=9r4c6 => -9r5c5; stte
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tlanglet



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

PostPosted: Tue Sep 25, 2012 8:13 pm    Post subject: Reply with quote

arkietech wrote:
tlanglet wrote:
The Type 4 UR(89) is an obvious solution but I enjoyed an almost AIC.

AAIC: {(4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7} = (9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7

Ted


Ted I am lost in your notation. Confused (1=8)r5c5 What happened to the 9

removing the 9 will solve the puzzle. Very Happy

(9=2)r3c5-r9c5=(2-5)r8c6=(5-9)r7c6=9r4c6 => -9r5c5; stte


Dan,

I treat all "almost" pattern the same way; determine the deletions of the basic pattern, then determine the deletions of the "almost" component(s) and take the deletions common to both steps. Note that a strong link exists between the basic pattern and the "almost" component(s); one or the other must be true;

Consider the finned x-wing; it is an "almost" pattern. We may mechanically take a short cut and directly delete the appropriate one or two cells in the box shared by the fin, but the logic is as previously mentioned. First we determine those cells deleted by the basic x-wing pattern and then we determine the cells deleted by the fin(s); the common deletions are then taken. I have frequently transported the fin and found additional deletions common with the x-wing.

Notational, I have been noting the strong link between the two parts with the basic pattern in curly brackets, {}, and then the AIC of the almost component.

{basic pattern} = AIC component

I recently asked RonK to comment on a notation for this condition but he did not have an alternate suggestion.

So, the answer to your question "What happened to the 9" is that it is dealt with by (9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7. I believe this post is particularly awkward because the basic pattern is also an AIC.

In an attempt to summarize, either the basic pattern is true or the almost component is true and I notate the pattern as a strong link between the two parts.

Ted
(I think it is time for some fruit of the vine!)
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Luke451



Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California

PostPosted: Tue Sep 25, 2012 9:15 pm    Post subject: Reply with quote

Hey, Ted, how are you?

I glad you had fun with the AAIC, needed or not! I'm terrible at finding those and I always end up poring over the puzzle when others post them to figure them out. A couple things.

First, I think if an AAIC component is comprised of an identifiable pattern, then that pattern should be noted with a label. In this case, we're looking at an XY chain, so stick that in there before the brackets. Not everyone is familiar with AAICs, but I'll bet a lot know what an XY chain is.

The only other thing is the brackets themselves. Curly brackets are seldom used. There was a time where they did not always display correctly, so [straight brackets] ended up becoming the norm.

Check out this treatment from one of our great manual solvers.
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tlanglet



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

PostPosted: Tue Sep 25, 2012 10:17 pm    Post subject: Reply with quote

Luke451 wrote:
Hey, Ted, how are you?

I glad you had fun with the AAIC, needed or not! I'm terrible at finding those and I always end up poring over the puzzle when others post them to figure them out. A couple things.

First, I think if an AAIC component is comprised of an identifiable pattern, then that pattern should be noted with a label. In this case, we're looking at an XY chain, so stick that in there before the brackets. Not everyone is familiar with AAICs, but I'll bet a lot know what an XY chain is.

The only other thing is the brackets themselves. Curly brackets are seldom used. There was a time where they did not always display correctly, so [straight brackets] ended up becoming the norm.

Check out this treatment from one of our great manual solvers.


Wonderful feedback Luke. J. C.s examples were also great.

Ted
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arkietech



Joined: 31 Jul 2008
Posts: 1687
Location: Northwest Arkansas USA

PostPosted: Tue Sep 25, 2012 10:33 pm    Post subject: Reply with quote

tlanglet wrote:
(I think it is time for some fruit of the vine!)

Good Idea Ted. Very Happy

After much thought (difficult for me) here is what I come up with:

(18A=9B)r5c5 => -4r1c7
A: (4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7 => -4r1c7
B: (9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7 => -4r1c7
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Wed Sep 26, 2012 12:34 am    Post subject: Reply with quote

Ted,

I know that you like to show your results as a single chain, but I always end up translating them for a better understanding. Given the amount of discussions your chains generate, I can't help but wonder if others must do so as well.


AAIC: {(4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7} = (9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7


I typically do two different translations on your chain.

Code:
Translation #1: One of two alternatives must be true.

XY-Chain: (4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7; -4r1c7
   ||
(9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7

Code:
Translation #2: Kraken Cell

(1)r5c5-(1=4)r1c5; -4r1c7
    ||
(8)r5c5-(8=3)r5c8-(3=4)r6c7; -4r1c7
    ||
(9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7


The benefit of these translations is that the eliminations are specifically derived for each segment extracted from your chain.
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tlanglet



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

PostPosted: Wed Sep 26, 2012 2:05 am    Post subject: Reply with quote

arkietech wrote:
tlanglet wrote:
(I think it is time for some fruit of the vine!)

Good Idea Ted. Very Happy

After much thought (difficult for me) here is what I come up with:

(18A=9B)r5c5 => -4r1c7
A: (4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7 => -4r1c7
B: (9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7 => -4r1c7


Yes, that is correct! Either A or B is correct => remove common deletions.

Ted
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tlanglet



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

PostPosted: Wed Sep 26, 2012 2:10 am    Post subject: Reply with quote

daj95376 wrote:
Ted,

I know that you like to show your results as a single chain, but I always end up translating them for a better understanding. Given the amount of discussions your chains generate, I can't help but wonder if others must do so as well.


AAIC: {(4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7} = (9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7


I typically do two different translations on your chain.

Code:
Translation #1: One of two alternatives must be true.

XY-Chain: (4=1)r1c5-(1=8)r5c5-(8=3)r5c8-(3=4)r6c7; -4r1c7
   ||
(9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7

Code:
Translation #2: Kraken Cell

(1)r5c5-(1=4)r1c5; -4r1c7
    ||
(8)r5c5-(8=3)r5c8-(3=4)r6c7; -4r1c7
    ||
(9)r5c5-(9=2)r3c5-r9c5=(2-5)r8c6=(5-3)r8c8=r8c7-(3=4)r6c7; -4r1c7


The benefit of these translations is that the eliminations are specifically derived for each segment extracted from your chain.


Yes, I have been presenting my solutions in "Translation #1" format. Maybe I should include the common deletions in an initial statement of the technique, e.g. AAIC; -4r1c7, to help make it clear.

Ted
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Luke451



Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California

PostPosted: Thu Sep 27, 2012 12:19 am    Post subject: Reply with quote

I can see why the Kraken cell approach might be a better way to sort out an AAIC like this. Problem is, Kraken cell doesn't speak to how the move could be found in the first place. It's more of an after-the-fact restructuring.

If one looked at r5c5 in this puzzle, what sort of clue would start one out on an examination of the Kraken's tentacles? A guess, maybe? That don't sound so attractive to me.

On the other hand, if a player looking for patterns noticed, "Hey, except for that (9)r5c5 there'd be an XY chain." Or a W-wing or a fish or whatever AIC. So bam, there's a potentially useful link that wasn't so obvious a second ago. That a pattern "almost" exists can be just as useful as a naked one.

If the AAIC approach is how one finds a move, then I don't see any problem with a single-line expression of it.
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tlanglet



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

PostPosted: Thu Sep 27, 2012 2:08 am    Post subject: Reply with quote

Luke,

I can't express my great appreciation for your comment about my AAIC solution for the Vanhegan Extreme September 25 puzzle. Your comments encourage me to continue posting on this site; I have seriously considered stopping.

If your travels bring you to the Sacramento area, I am just a short distance away and would truly enjoy meeting you.

Ted
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arkietech



Joined: 31 Jul 2008
Posts: 1687
Location: Northwest Arkansas USA

PostPosted: Thu Sep 27, 2012 2:28 am    Post subject: Reply with quote

tlanglet wrote:
Luke,

I can't express my great appreciation for your comment about my AAIC solution for the Vanhegan Extreme September 25 puzzle. Your comments encourage me to continue posting on this site; I have seriously considered stopping.

If your travels bring you to the Sacramento area, I am just a short distance away and would truly enjoy meeting you.

Ted


Ted

Your solutions have been a great help to me and I look forward to them.

Thanks for your help when I get lost.

If you are ever in Northwest Arkansas let us share a little fruit of the vine
.
Dan
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aran



Joined: 19 Apr 2010
Posts: 70

PostPosted: Thu Sep 27, 2012 2:25 pm    Post subject: Reply with quote

On the matter of notation for almost structures :
the basic form is always :
Almost Element=Structure
or its equivalent
Structure=Almost Element
this form then develops into
[AE-.....=>z] = [S=>z] : => z.
Starting from there, some considerations on notation :
1. preference should be for the former version AE=S, since it immediately introduces the Almost Element, and therefore points the reader, if there is one, in the right direction at the outset
2. there is no escaping the fact that the logic for the conclusion z is that it is implied by both terms AE and S. To that extent, there might be an argument for making this clear by showing z as the conclusion of each term (rather than have the reader deduce this from a more concise version of each term)
3. using brackets to surround each term would probably add to clarity.
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Luke451



Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California

PostPosted: Wed Oct 03, 2012 6:55 pm    Post subject: Reply with quote

tlanglet wrote:
If your travels bring you to the Sacramento area, I am just a short distance away and would truly enjoy meeting you.

Just saw this, Ted, thanks for the invite!

If you travel to the Bay, I welcome you to one of our IPA tasting soirčes (India Pale Ale.) Venue: north terraces every Earthquakes home match, Santa Clara, Ca.
Dress code, casual... Twisted Evil


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