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telegraph 12-10-2010

 
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Sat Dec 11, 2010 9:55 am    Post subject: telegraph 12-10-2010 Reply with quote

300200005090003760080009030000602000230000050000800000070500090054100070000006000

Code:

+-------+-------+-------+
| 3 . . | 2 . . | . . 5 |
| . 9 . | . . 3 | 7 6 . |
| . 8 . | . . 9 | . 3 . |
+-------+-------+-------+
| . . . | 6 . 2 | . . . |
| 2 3 . | . . . | . 5 . |
| . . . | 8 . . | . . . |
+-------+-------+-------+
| . 7 . | 5 . . | . 9 . |
| . 5 4 | 1 . . | . 7 . |
| . . . | . . 6 | . . . |
+-------+-------+-------+

Play online
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peterj



Joined: 26 Mar 2010
Posts: 974
Location: London, UK

PostPosted: Sat Dec 11, 2010 4:54 pm    Post subject: Reply with quote

I did this one on the tube in the newspaper using ink pen - so I was quite pleased to catch this MUG (I think it is anyway) Exclamation
Not the shortest path I am sure...
Code:
 *------------------------------------------------------------*
 | 3     (46)  7     | 2     68    1     | 9      (48)  5     |
 | 15    9     125   | 4     58    3     | 7      6     128   |
 | 145   8     1256  | 7     56    9     | (14)   3     124   |
 |-------------------+-------------------+--------------------|
 | 579   *14   59    | 6     *134  2     | *34+18 14-8  79    |
 | 2     3     8     | 9     14    7     | 146    5     146   |
 | 479   *14+6 69    | 8     *134  5     | *34+1  2     79    |
 |-------------------+-------------------+--------------------|
 | 18    7     3     | 5     2     4     | 168    9     168   |
 | 6     5     4     | 1     9     8     | 2      7     3     |
 | 189   2     19    | 3     7     6     | 5      148   148   |
 *-----------------------------------------------------------*

6-Cell MUG(134) r46c257
(6)r6c2   - (6=4)r1c2 - (4=8)r1c8 ; r4c8<>8
(1)r46c7  - (1=4)r3c7 - (4=8)r1c8 ; r4c8<>8
(8)r4c7                           ; r4c8<>8

I think I used a couple of xy-wings after that...
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

PostPosted: Sun Dec 12, 2010 12:28 am    Post subject: Reply with quote

From the posted grid, a Type 4 UR on 79 in boxes 46 will finish things off. R46c1<>9.
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Sun Dec 12, 2010 1:30 am    Post subject: Reply with quote

Peter,

Wonderful find. I found the Type 4 UR(79) but missed that wonderful MUG(134).

I believe the only free digits in the MUG are r6c2=4 and r4c7=8. The 1s in r46c7 are part of the MUG and therefore not free digits; you did treat the 1s in r46c5 as part of the MUG.

Ted
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Sun Dec 12, 2010 1:51 am    Post subject: Reply with quote

tlanglet wrote:
Peter,

Wonderful find. I found the Type 4 UR(79) but missed that wonderful MUG(134).

I believe the only free digits in the MUG are r6c2=6 and r4c7=8. The 1s in r46c7 are part of the MUG and therefore not free digits; you did treat the 1s in r46c5 as part of the MUG.

Ted, I thought the same about the 1s in r46c7, but I then spent an hour persuading myself that I was wrong and that Peter was correct. The wrinkle comes in the form of secondary effects on r5c5=14 caused by the X-Wing on <3>. The only way around it is to expand the scope of the DP:

Code:
 *-------------------------------------------------------------*
 | 3     (46)  7     | 2     68    1     |  9      (48)  5     |
 | 15    9     125   | 4     58    3     |  7      6     128   |
 | 145   8     1256  | 7     56    9     |  (14)   3     124   |
 |-------------------+-------------------+---------------------|
 | 579  *14    59    | 6    *134   2     | *134+8  14-8  79    |
 | 2     3     8     | 9    *14    7     | *14+6   5     146   |
 | 479  *14+6  69    | 8    *134   5     | *134    2     79    |
 |-------------------+-------------------+---------------------|
 | 18    7     3     | 5     2     4     |  168    9     168   |
 | 6     5     4     | 1     9     8     |  2      7     3     |
 | 189   2     19    | 3     7     6     |  5      148   148   |
 *-------------------------------------------------------------*

... and then I can't get the stinkin' r5c7=6 to produce r4c8<>8. Mad


Last edited by daj95376 on Sun Dec 12, 2010 1:57 am; edited 1 time in total
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Sun Dec 12, 2010 1:53 am    Post subject: Reply with quote

Since Marty had already posted my initial solution, I made a second pass and found this one step solution.

Quote:
ANP(15=4)r23c1-(4=6)r1c2-(6=8)r1c5-(8=5)r2c5*-(5=1)r2c1; r2c3<>5*, r79c1<>1

Ted
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peterj



Joined: 26 Mar 2010
Posts: 974
Location: London, UK

PostPosted: Sun Dec 12, 2010 9:42 am    Post subject: Reply with quote

daj95376 wrote:
Ted, I thought the same about the 1s in r46c7, but I then spent an hour persuading myself that I was wrong and that Peter was correct.

The first time I played it as if the 1s were part of the MUG but before I posted it I re-read Myth Jellies et al post on MUG - specifically this post which suggests a MUG is valid if it's an overlay of multiple BUG-Lites.. and seems to rule out the case
Code:
ab | abc | abc
ab | abc | abc

whereas
Code:
ab | abc | bc
ab | abc | bc

is clearly an overlay of a (ab)UR and (bc(UR).
I still don't really understand this! It would be great if someone could come up with a practical rule for testing a proposed MUG!
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ronk



Joined: 07 May 2006
Posts: 398

PostPosted: Sun Dec 12, 2010 12:08 pm    Post subject: Reply with quote

peterj wrote:
It would be great if someone could come up with a practical rule for testing a proposed MUG!

If a BUG-Lite is the result of all possible reductions of a prospective MUG, whether fully or partially populated, then the prospective MUG is an actual MUG.

Code:

A fully populated MUG:
 .   abc .   | .   abc .   | .   abc .   
 .   .   .   | .   .   .   | .   .   .   
 .   abc .   | .   abc .   | .   abc .   
-------------+-------------+-------------

One of its six possible BUG-Lites:
 .   ab  .   | .   ac  .   | .   bc  .   
 .   .   .   | .   .   .   | .   .   .   
 .   ab  .   | .   ac  .   | .   bc  .   
-------------+-------------+-------------

[edit: Sentence was "If a prospective MUG, whether fully or partially populated, can be reduced to a BUG-Lite, it is an actual MUG."]


Last edited by ronk on Sun Dec 12, 2010 3:57 pm; edited 1 time in total
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peterj



Joined: 26 Mar 2010
Posts: 974
Location: London, UK

PostPosted: Sun Dec 12, 2010 3:32 pm    Post subject: Reply with quote

ronk wrote:
If a prospective MUG, whether fully or partially populated, can be reduced to a BUG-Lite, it is an actual MUG.

Thanks, ronk, but surely that is not sufficient?

It is a MUG if valid reductions lead only to one or more BUG-lite/URs?

For example,
Code:
abc | abc
abc | abc
is not a MUG. Placing an (a) externally in each column reduces it to a DP.
Code:
bc | bc
bc | bc
However, placing an (a) externally in row 1 and an (b) in row 2 produces
Code:
bc | bc
ac | ac
and (a) externally in column 1 results in
Code:
b | c
c | a
which is obviously valid?

So if that is right we are still left with having to test all possible reductions of the pattern from external placements to check if they result in a recognisable DP.
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ronk



Joined: 07 May 2006
Posts: 398

PostPosted: Sun Dec 12, 2010 3:51 pm    Post subject: Reply with quote

peterj wrote:
ronk wrote:
If a prospective MUG, whether fully or partially populated, can be reduced to a BUG-Lite, it is an actual MUG.

Thanks, ronk, but surely that is not sufficient?
...
So if that is right we are still left with having to test all possible reductions of the pattern from external placements to check if they result in a recognisable DP.

Yes, all possible reductions of a MUG must lead to a BUG-Lite.
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