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One-Trick Pony

 
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Ruud



Joined: 18 Jan 2006
Posts: 31

PostPosted: Tue Aug 21, 2007 9:48 pm    Post subject: One-Trick Pony Reply with quote

Here is a puzzle from the long forgotten top95.

Code:
4 8 .|3 . .|. . .
. . .|. . .|. 7 1
. 2 .|. . .|. . .
-----+-----+-----
7 . 5|. . .|. 6 .
. . .|2 . .|8 . .
. . .|. . .|. . .
-----+-----+-----
. . 1|. 7 6|. . .
3 . .|. . .|4 . .
. . .|. 5 .|. . .

The challenge:

Solve this puzzle using only singles, intersections, pairs, and a single advanced move.

There may be several alternative moves that you can choose from, but I wonder if you can find that one special move.

Ruud
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Tue Aug 21, 2007 11:08 pm    Post subject: Reply with quote

I've no idea but as it's you I shall say Death Blossom somewhere ?
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keith



Joined: 19 Sep 2005
Posts: 3350
Location: near Detroit, Michigan, USA

PostPosted: Tue Aug 21, 2007 11:57 pm    Post subject: Reply with quote

My opinion: A very unpleasant puzzle, for those of us who are inveterate pencil & paper solvers.

Keith
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Ruud



Joined: 18 Jan 2006
Posts: 31

PostPosted: Wed Aug 22, 2007 5:17 pm    Post subject: Reply with quote

This is a very deceiving puzzle.

You need 2 naked pairs and 4 hidden pairs to get to this point:

Code:
.------------------.------------------.------------------.
| 4     8     7    | 3     12    12   | 56    9     56   |
| 59    359   39   | 6     48    48   | 2     7     1    |
| 1     2     6    | 57    9     57   | 3     8     4    |
:------------------+------------------+------------------:
| 7     34    5    | 89    348   489  | 1     6     2    |
| 69    13469 349  | 2     1346  57   | 8     34    57   |
| 28    1346  28   | 57    1346  14   | 57    34    9    |
:------------------+------------------+------------------:
| 58    45    1    | 48    7     6    | 9     2     3    |
| 3     67    89   | 1     28    289  | 4     5     67   |
| 269   4679  249  | 49    5     3    | 67    1     8    |
'------------------'------------------'------------------'

Now you can make your move. No Death Blossom. No chain.

Ruud
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TKiel



Joined: 22 Feb 2006
Posts: 292
Location: Kalamazoo, MI

PostPosted: Wed Aug 22, 2007 7:05 pm    Post subject: Reply with quote

My hat is off to the pencil and paper people who slogged through this. Salute!

Ruud wrote:
Now you can make your move.


How come every time I try a move , the defense slams the ball back in my face?
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Ruud



Joined: 18 Jan 2006
Posts: 31

PostPosted: Wed Aug 22, 2007 10:20 pm    Post subject: Reply with quote

Hint:
.------------------.------------------.------------------. 

| 4 8 7 | 3 12 12 | 56 9 56 |
| 59 359 39 | 6 48 48 | 2 7 1 |
| 1 2 6 | 57 9 57 | 3 8 4 |
:------------------+------------------+------------------:
| 7 34 5 | 89 348 489 | 1 6 2 |
| 69 13469 349 | 2 1346 57 | 8 34 57 |
| 28 1346 28 | 57 1346 14 | 57 34 9 |
:------------------+------------------+------------------:
| 58 45 1 | 48 7 6 | 9 2 3 |
| 3 67 89 | 1 28 289 | 4 5 67 |
| 269 4679 249 | 49 5 3 | 67 1 8 |
'------------------'------------------'------------------'
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Thu Aug 23, 2007 10:15 am    Post subject: Reply with quote

67 can not exist in r9c2 - all the other pairs are locked in. Is this in someway bug related ?
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Ruud



Joined: 18 Jan 2006
Posts: 31

PostPosted: Thu Aug 23, 2007 5:26 pm    Post subject: Reply with quote

This move is called BUG-Lite.

A size 12 Deadly Pattern is very rare.

Ruud
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Fri Aug 24, 2007 6:41 am    Post subject: Reply with quote

Many thanks for sharing that.
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Hasel



Joined: 23 Aug 2007
Posts: 4

PostPosted: Fri Aug 24, 2007 12:33 pm    Post subject: Reply with quote

That was tough ,, but i did it .







Hasel
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Ruud



Joined: 18 Jan 2006
Posts: 31

PostPosted: Fri Sep 07, 2007 2:12 pm    Post subject: New Trick Reply with quote

Here is another One-Trick Pony.

A rather nice step cracks the puzzle, but there is a less elegant alternative that achieves the same result.
Code:
1 9 .|. 5 .|. . 4
. . 7|. . .|3 . .
. . .|9 . 3|. 2 5
-----+-----+-----
. 8 .|. . 6|. . 2
. . .|. 4 .|. . .
3 . .|8 . .|. 1 .
-----+-----+-----
6 3 .|1 . 7|. . .
. . 8|. . .|5 . .
7 . .|. 8 .|. 3 1

Ruud
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Johan



Joined: 25 Jun 2007
Posts: 206
Location: Bornem Belgium

PostPosted: Fri Sep 07, 2007 6:04 pm    Post subject: Reply with quote

Quote:

A rather nice step cracks the puzzle

This is the grid after basic steps
Code:

+----------------+--------------+----------------+
| 1   9     3    |*26   5  28   | 678  678   4   |
| 25  25    7    |*46   16 148  | 3    689   689 |
| 8   46    46   | 9    7  3    | 1    2     5   |
+----------------+--------------+----------------+
| 459 8     149  | 357  13 6    | 479  4579  2   |
| 259 2567  1269 | 257  4  1259 | 6789 56789 3   |
| 3   24567 2469 | 8    29 259  | 4679 1     679 |
+----------------+--------------+----------------+
| 6   3     5    | 1    29 7    | 2489 489   89  |
| 249 1     8    |*2346 *36 249 | 5    679   679 |
| 7   24    249  | 245-6 8 2459 | 269  3     1   |
+----------------+--------------+----------------+


There is an WXYZ-wing with pivot in R8C4 which eliminates <6> in R9C4.

The common number (Z) or <6> can only reside in R1C4, R2C4, R8C4 or R8C5.
R9C4 contains a <6> that can see the other four cells (R1C4, R2C4, R8C4 and R8C5), so <6> can be erased from R9C4, and the puzzle collapses.

Never encountered this step before in a previous puzzle, but like Ruud said a very nice step to crack this one.
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Steve R



Joined: 24 Oct 2005
Posts: 289
Location: Birmingham, England

PostPosted: Sat Sep 08, 2007 12:30 am    Post subject: Reply with quote

Johan,

Yes, thatís my preferred solution too. If you have not seen it, may I recommend bennysís original paper on almost locked sets? It is a model of clarity, effectively covering every known xyÖetc wing in one fell swoop. (The endorsement does not extend to the rest of the thread, which adds little you will not be able to work out for yourself).

The question remains as to whether this approach satisfies Ruudís criteria of elegance. I have a sneaking suspicion that he might be attracted by a uniqueness argument, even if, so to speak, it is in reverse.

Steve
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Johan



Joined: 25 Jun 2007
Posts: 206
Location: Bornem Belgium

PostPosted: Sun Sep 09, 2007 12:33 am    Post subject: Reply with quote

Quote:
may I recommend bennysís original paper on almost locked sets


Steve,

Thanks for the useful ALS info from bennys's original paper.

Reading this ALS topic more than once, I conclude that the eliminations are based upon the restricted common candidate (in the wxyz-wing with pivot in R8C4, <6> is restricted common.)

Though in this wxyz-wing example with a four-value pivot and three bi-value cells lined up in a L-shape, was not so hard to spot, finding a restricted common candidate in ALS-cells which have more than two or three values in one cell,and are arbitrary lined up in the grid, is much harder to detect IMO.


Johan,
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Sun Sep 09, 2007 8:32 pm    Post subject: Reply with quote

I often assume on the extreme puzzles that where an ALS elimination is likely to occur one of the ALS's is usually a bivalue. This often works.

When this doesn't work, one can build out from there. A sort of reverse engineer. I look for the eliminands then go back and find the restricted common candidate between the sets which supports/denies the elimination.
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