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Another Vanhagen Extreme

 
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Sat Nov 19, 2011 3:40 pm    Post subject: Another Vanhagen Extreme Reply with quote
Code:

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

Play online

My first four steps were

anp(19=6)r41c2-(6=7=1)r1c48-(1=4)r6c8-r6c1=r4c2; r4c2<>19

(6)r4c6=(6)r23c6-(6=7)r1c4-(7=1)r1c8-(1=4)r6c8-r6c1=r4c2;4c2<>6

color (6); r3c3<>6

color(9); r4c3<>9

The resultant code is
Code:
*--------------------------------------------------*
 | 2    19   4    | 67   5    3    | 8    17   69   |
 | 67   5    3    | 9    8    167  | 2    17   4    |
 | 67   8    19   | 4    2    167  | 69   5    3    |
 |----------------+----------------+----------------|
 | 3    4    16   | 2    7    56   | 159  8    19   |
 | 5    7    8    | 1    9    4    | 3    6    2    |
 | 19   2    169  | 56   3    8    | 15   4    7    |
 |----------------+----------------+----------------|
 | 8    3    2    | 57   4    57   | 16   9    16   |
 | 19   19   7    | 8    6    2    | 4    3    5    |
 | 4    6    5    | 3    1    9    | 7    2    8    |
 *--------------------------------------------------*


I viewed this code as a BUG+4 condition which results in the following strong inferences: r2c6=7, r3c6=6, r4c7=1, r6c3=1

However, I was not able to find a common resolution. Is this a valid BUG+4?

I completed the puzzle with an anp(15=9)r64c7-(5)r4c7=r4c6-(5=6)r6c4-(6=7)r1c4-(7=1=9=6)r1c4829-(6=1)r7c9; r4c9<>1

Ted
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ronk



Joined: 07 May 2006
Posts: 398
PostPosted: Sat Nov 19, 2011 7:54 pm    Post subject: Re: Another Vanhagen Extreme Reply with quote
tlanglet wrote:
The resultant code is
Code:

 *--------------------------------------------------*
 | 2    19   4    |*67   5    3    | 8    17   69   |
 | 67   5    3    | 9    8    16+7 | 2    17   4    |
 | 67   8    19   | 4    2    1-7+6| 69   5    3    |
 |----------------+----------------+----------------|
 | 3    4    16   | 2    7    56   | 59+1 8    19   |
 | 5    7    8    | 1    9    4    | 3    6    2    |
 | 19   2    69+1 |*56   3    8    |*15   4    7    |
 |----------------+----------------+----------------|
 | 8    3    2    | 57   4    57   | 16   9    16   |
 | 19   19   7    | 8    6    2    | 4    3    5    |
 | 4    6    5    | 3    1    9    | 7    2    8    |
 *--------------------------------------------------*


I viewed this code as a BUG+4 condition which results in the following strong inferences: r2c6=7, r3c6=6, r4c7=1, r6c3=1

However, I was not able to find a common resolution. Is this a valid BUG+4?

This is indeed a valid BUG+4. The first exclusion I see is:
Code:
BUG+4
 ||
(6)r3c6
 ||
(7)r2c6
 ||
(1)[r4c7|r6c3] - (1=5)r6c7 - (5=6)r6c4 - (6=7)r1c4 ==> r3c6<>7
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Sun Nov 20, 2011 1:01 am    Post subject: Reply with quote
Ron,

I obviously missed the resolution you posted; thanks for the insight.

Question: Does a common resolution exist for every valid BUG, or are some BUG patterns just not resolvable?

Ted
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ronk



Joined: 07 May 2006
Posts: 398
PostPosted: Sun Nov 20, 2011 4:45 am    Post subject: Reply with quote
tlanglet wrote:
Question: Does a common resolution exist for every valid BUG, or are some BUG patterns just not resolvable?

My guess is a resolution always exists. However, as the 'n' of 'BUG+n' increases, resolutions quickly become too complicated to be practical.
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Sun Nov 20, 2011 2:25 pm    Post subject: Reply with quote
ronk wrote:
tlanglet wrote:
Question: Does a common resolution exist for every valid BUG, or are some BUG patterns just not resolvable?

My guess is a resolution always exists. However, as the 'n' of 'BUG+n' increases, resolutions quickly become too complicated to be practical.


The next time I run across a BUG+4, I will try to resolve it. For anything larger (n>4) I will look for another step.

Ted
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ronk



Joined: 07 May 2006
Posts: 398
PostPosted: Sun Nov 20, 2011 5:14 pm    Post subject: Reply with quote
tlanglet wrote:
The next time I run across a BUG+4, I will try to resolve it. For anything larger (n>4) I will look for another step.

Sounds like a reasonable plan to me. However, if you posted some of those with n>4, it might be educational for us all. They might not be as tough as we think.
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