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Interesting Menneske

 
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA
PostPosted: Sat Nov 26, 2011 3:31 pm    Post subject: Interesting Menneske Reply with quote
Code:
Puzzle: M5073730sh(20)
+-------+-------+-------+
| 4 9 . | 2 . 3 | . . 7 |
| . . . | . . 7 | 4 1 . |
| . . . | . 9 . | . . 5 |
+-------+-------+-------+
| . . . | . 8 . | 2 4 . |
| 7 . . | . . 4 | . . . |
| . . 3 | . 1 6 | . . . |
+-------+-------+-------+
| . 1 . | . . . | . 3 . |
| 6 3 . | . . . | 7 5 . |
| . . . | . . . | . . . |
+-------+-------+-------+

Keith
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daj95376



Joined: 23 Aug 2008
Posts: 3854
PostPosted: Sat Nov 26, 2011 7:02 pm    Post subject: Reply with quote
This doesn't do anything important, but I found it to be an interesting UR pattern.

Code:
 after basics
 +---------------------------------------------------------------+
 |  4     9     1     |  2     5     3     | *68    *68    7     |
 |  3     25    25    |  8     6     7     |  4      1     9     |
 |  8     67    67    |  4     9     1     |  3      2     5     |
 |--------------------+--------------------+---------------------|
 |  1     56    569   |  7     8     59    |  2      4     3     |
 |  7     58    589   |  3     2     4     |  1569   69    16    |
 |  2     4     3     |  59    1     6     |  59     7     8     |
 |--------------------+--------------------+---------------------|
 |  59    1     248   |  56    7     258   | #68+9   3     246   |
 |  6     3     28    |  19    4     289   |  7      5     12    |
 |  59    278   2478  |  156   3     258   | *68+19 *68+9  1246  |
 +---------------------------------------------------------------+
 # 53 eliminations remain

 r9c8<>9  =>       UR Type 1         =>  r9c7<>68
 r9c8= 9  =>  <68> Naked Pair r17c7  =>  r9c7<>68

AKA a specific perspective of Mike Barker's UR+2kx pattern.
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Sat Nov 26, 2011 11:56 pm    Post subject: Reply with quote
I don't think I found this interesting in the sense that you did. I couldn't see any conventional moves and had to settle for an XY-Chain. The 9 in r8c4 proves 1 in r5c9; r8c9<>1.
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Sun Nov 27, 2011 3:28 pm    Post subject: Reply with quote
Marty,

I think you found the big winner. I noticed a couple of other chains but they did not do any real damage.

Ted
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Sun Nov 27, 2011 6:04 pm    Post subject: Reply with quote
Thanks Ted. I'm always happy whenever I can solve a puzzle, but chains don't satisfy me as much as the pattern-based techniques. Chains have a trial-and-error feel to them because I'm just trying things to see if anything happens.
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA
PostPosted: Sun Nov 27, 2011 6:47 pm    Post subject: Reply with quote
Marty,

If you regard R5C89 as a pseudo-cell 19, your chain looks like a W-wing 19 - 59 - 59 - 19, so it's almost a pattern.

I thought I had a couple of wings that knocked out 5 in R79C6, but now I cannot find one of them.

Keith
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Sun Nov 27, 2011 10:34 pm    Post subject: Reply with quote
Nice spot Keith. Unfortunately, I can't find pseudo cells other than in a UR. Embarassed Sad
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daj95376



Joined: 23 Aug 2008
Posts: 3854
PostPosted: Mon Nov 28, 2011 12:03 am    Post subject: Reply with quote
keith wrote:
I thought I had a couple of wings that knocked out 5 in R79C6, but now I cannot find one of them.

There is an M-Wing for r9c6<>5.

Code:
 +--------------------------------------------------------------+
 |  4     9     1     |  2     5     3     |  68    68    7     |
 |  3     25    25    |  8     6     7     |  4     1     9     |
 |  8     67    67    |  4     9     1     |  3     2     5     |
 |--------------------+--------------------+--------------------|
 |  1     56    569   |  7     8    f59    |  2     4     3     |
 |  7     58    589   |  3     2     4     |  1569  69    16    |
 |  2     4     3     | e59    1     6     | d59    7     8     |
 |--------------------+--------------------+--------------------|
 | b59    1     248   |  56    7     258   | c689   3     246   |
 |  6     3     28    |  19    4     289   |  7     5     12    |
 | a59    278   2478  |  156   3     258   |  1689  689   1246  |
 +--------------------------------------------------------------+
 # 53 eliminations remain

 M-Wing: (5=9)r9c1 - r7c1 = r7c7 - r6c7 = (9-5)r6c4 = (5)r4c6  =>  r9c6<>5

There may be an alternate path for both eliminations, but my solver only saves the shortest and most effective.

Code:
 +--------------------------------------------------------------+
 |  4     9     1     |  2     5     3     |  68    68    7     |
 |  3     25    25    |  8     6     7     |  4     1     9     |
 |  8     67    67    |  4     9     1     |  3     2     5     |
 |--------------------+--------------------+--------------------|
 |  1     56    569   |  7     8    a59    |  2     4     3     |
 |  7     58    589   |  3     2     4     | d1569  69    16    |
 |  2     4     3     | b9-5   1     6     | c59    7     8     |
 |--------------------+--------------------+--------------------|
 |  59    1     248   | f56    7     28-5  |  689   3     246   |
 |  6     3     28    |  19    4     289   |  7     5     12    |
 |  59    278   2478  | f56+1  3     28-5  | e1689  689   1246  |
 +--------------------------------------------------------------+
 # 53 eliminations remain

(5)r4c6 = r6c4 - r6c7 = (5-1)r5c7 = r9c7 - (1=56)r79c4  =>  r6c4,r79c6<>5

Regards, Danny
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA
PostPosted: Mon Nov 28, 2011 12:13 am    Post subject: Reply with quote
Danny,

I see why you'd find the M-wing first, but there is also a W-wing on those 59 cells. Look for the links on 9 in C38 or alternatively in R7C6.

It's eliminating 5 in R7C6 that eludes me. I have now convinced myself it cannot be done with a wing.

By the way, killing 9 in R4C6 accomplishes the same thing that I thought I saw.

Keith
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daj95376



Joined: 23 Aug 2008
Posts: 3854
PostPosted: Mon Nov 28, 2011 3:27 am    Post subject: Reply with quote
keith wrote:
Danny,

I see why you'd find the M-wing first, but there is also a W-wing on those 59 cells. Look for the links on 9 in C38 or alternatively in R7C6.

It's eliminating 5 in R7C6 that eludes me. I have now convinced myself it cannot be done with a wing.

By the way, killing 9 in R4C6 accomplishes the same thing that I thought I saw.

I have a special version of my solver where chains are restricted to containing only two values. Once these chains are collected, I make a pass through them and report all of the M-Wings. Then I make additional passes for W-Wing, S-Wing, and L-Wing. As long as the results are equally effective, it's "natural" for me to grab the first M-Wing listed (that matches eliminations reported by others).

My solver returned 30 M-Wings for r9c6<>5. It also returned 17 W-Wings for r9c6<>5. Finally, it returned 8 L-Wings for r5c3<>8.

Nowhere does it return r7c6<>5 as a wing. The same as your conclusion.

My second chain (in my second post) eliminates <5> in three cells, and is equivalent to r4c6=5<>9.

Regards, Danny
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Tue Nov 29, 2011 1:09 am    Post subject: Reply with quote
Have you Menneske users noticed the recent change whereby you no longer get Very Hards when clicking Super Hard? Now I can get a puzzle i want with just, say, 15 clicks instead of 30. Laughing
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