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Menneske 2897824

 
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arkietech



Joined: 31 Jul 2008
Posts: 1727
Location: Northwest Arkansas USA

PostPosted: Sun Oct 07, 2012 6:46 am    Post subject: Menneske 2897824 Reply with quote

Code:

 *-----------*
 |.8.|9..|.7.|
 |5.1|8..|2.3|
 |6..|3..|..8|
 |---+---+---|
 |...|.8.|521|
 |...|5.2|...|
 |254|.9.|...|
 |---+---+---|
 |8..|..9|..2|
 |1.5|..8|7.9|
 |.2.|..4|.6.|
 *-----------*

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Luke451



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

PostPosted: Sun Oct 07, 2012 2:45 pm    Post subject: Reply with quote

Lotsa ways home for this guy.

Code:
 *--------------------------------------------------*
 | 4    8    3    | 9    2    5    | 1    7    6    |
 | 5    79   1    | 8    467  67   | 2    49   3    |
 | 6    79   2    | 3    147  17   | 49   5    8    |
 |----------------+----------------+----------------|
 |*79+3 36  *79+6 | 4    8    37   | 5    2    1    |
 | 37   1    8    | 5    67   2    | 369  39   4    |
 | 2    5    4    | 16   9    136  | 36   8    7    |
 |----------------+----------------+----------------|
 | 8    34   67   | 67   5    9    | 34   1    2    |
 | 1    346  5    | 2    36   8    | 7    34   9    |
 |*79+3 2   *79   | 17   13   4    | 8    6    5    |
 *--------------------------------------------------*

Internal outs of (79)AUR:
(3=6)r4c2-(6)r3c3=(3)r49c1 ==>r5c1<>3

or maybe external:

"Unique" S-wing:
(7)r7c3=(7)r5c1-(7=6)r5c5-(6)r6c4=(6)r7c4 ==>r7c4<>7
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Marty R.



Joined: 12 Feb 2006
Posts: 5164
Location: Rochester, NY, USA

PostPosted: Sun Oct 07, 2012 4:21 pm    Post subject: Reply with quote

Code:
 *-----------------------------------------------------*
 |  4    8    3    |  9     2    5    | 1    7    6    |
 |  5    79   1    |  8     467  67   | 2    49   3    |
 |  6    79   2    |  3     147  17   | 49   5    8    |
 |-----------------+------------------+----------------|
 |  379  36  A679  |  4     8    37   | 5    2    1    |
 | B37   1    8    |  5    C67   2    | 369  39   4    |
 |  2    5    4    | D16    9    136  | 36   8    7    |
 |-----------------+------------------+----------------|
 |  8    34  -67   | E67    5    9    | 34   1    2    |
 |  1    346  5    |  2     36   8    | 7    34   9    |
 |  379  2    79   |  17    13   4    | 8    6    5    |
 *-----------------------------------------------------*


I also used the DP 79. Either r49c1=3-->r5c1=7(B) or r4c3=6(A). B=7-->E=6 via BCDE; r7c3<>6.
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arkietech



Joined: 31 Jul 2008
Posts: 1727
Location: Northwest Arkansas USA

PostPosted: Sun Oct 07, 2012 6:40 pm    Post subject: Reply with quote

aur externals still mystify me! Confused


so I am back to "almost" xy-wings:

Code:

 *--------------------------------------------------*
 | 4    8    3    | 9    2    5    | 1    7    6    |
 | 5    79   1    | 8   c467  67   | 2   b49   3    |
 | 6    79   2    | 3    147  17   | 49   5    8    |
 |----------------+----------------+----------------|
 | 379  36   679  | 4    8    37   | 5    2    1    |
 | 37   1    8    | 5   c67   2    | 369 a39   4    |
 | 2    5    4    | 16   9    136  | 36   8    7    |
 |----------------+----------------+----------------|
 | 8    34   67   | 67   5    9    | 34   1    2    |
 | 1    346  5    | 2   c36   8    | 7    4-3  9    |
 | 379  2    79   | 17   13   4    | 8    6    5    |
 *--------------------------------------------------*
als xy-wing
(3=9)r5c8-(9=4)r2c8-(4=3)als:r258c5 => -3r8c8; stte



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ronk



Joined: 07 May 2006
Posts: 397

PostPosted: Mon Oct 08, 2012 12:23 am    Post subject: Reply with quote

Luke451 wrote:
Code:
 *--------------------------------------------------*
 | 4    8    3    | 9    2    5    | 1    7    6    |
 | 5    79   1    | 8    467  67   | 2    49   3    |
 | 6    79   2    | 3    147  17   | 49   5    8    |
 |----------------+----------------+----------------|
 |*79+3 36  *79+6 | 4    8    37   | 5    2    1    |
 | 37   1    8    | 5    67   2    | 369  39   4    |
 | 2    5    4    | 16   9    136  | 36   8    7    |
 |----------------+----------------+----------------|
 | 8    34   67   | 67   5    9    | 34   1    2    |
 | 1    346  5    | 2    36   8    | 7    34   9    |
 |*79+3 2   *79   | 17   13   4    | 8    6    5    |
 *--------------------------------------------------*

Two moves using UR(79)r49c13 can be applied simultaneously:
    overlapping x-wing for digit 9 ==> r4c1<>7
    external DP busters (7)r5c1 = (7)r7c3 ==> r4c3<>7
    stte
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arkietech



Joined: 31 Jul 2008
Posts: 1727
Location: Northwest Arkansas USA

PostPosted: Mon Oct 08, 2012 1:51 am    Post subject: Reply with quote

ronk wrote:
external DP busters (7)r5c1 = (7)r7c3 ==> r4c3<7>


(7=3)r5c1-(3=6)aur:r49c13 => -7r4c3

3 in r5c1 forces a 6 in r4c3 due to the dp

Thanks ronk!
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Luke451



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

PostPosted: Mon Oct 08, 2012 5:34 am    Post subject: Reply with quote

arkietech wrote:
ronk wrote:
external DP busters (7)r5c1 = (7)r7c3 ==> r4c3<7>


(7=3)r5c1-(3=6)aur:r49c13 => -7r4c3

3 in r5c1 forces a 6 in r4c3 due to the dp

I think it's simpler than that. Simpler than any of the UR related moves offered above, including my own.
Ron is pointing out that the (79) UR solves the puzzle without the need for a chain at all.
Code:
 *--------------------------------------------------*
 | 4    8    3    | 9    2    5    | 1    7    6    |
 | 5    79   1    | 8    467  67   | 2    49   3    |
 | 6    79   2    | 3    147  17   | 49   5    8    |
 |----------------+----------------+----------------|
 |*79+3 36  *79+6 | 4    8    37   | 5    2    1    |
 | 37   1    8    | 5    67   2    | 369  39   4    |
 | 2    5    4    | 16   9    136  | 36   8    7    |
 |----------------+----------------+----------------|
 | 8    34   67   | 67   5    9    | 34   1    2    |
 | 1    346  5    | 2    36   8    | 7    34   9    |
 |*79+3 2   *79   | 17   13   4    | 8    6    5    |
 *--------------------------------------------------*

There's a hidden rectangle that takes out (7)r4c1 due to the x-wing overlay on (9) and the naked (79)r9c3.
More simply, if the (7) ended up in r4c1, the DP would be forced:
Code:
7   9
9   7

At the same time, the "external outs" (7r5c1 = 7r7c3) pinch off (7)r4c3.
Each condition exists independently, but when both are applied they solve the puzzle.
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keith



Joined: 19 Sep 2005
Posts: 3179
Location: near Detroit, Michigan, USA

PostPosted: Mon Oct 08, 2012 10:23 am    Post subject: Reply with quote

The X-wing overlaying a UR has been called a "Type 6" UR.
Code:
+-------------+-------------+-------------+
| 4   8   3   | 9   2   5   | 1   7   6   |
| 5   79  1   | 8   467 67  | 2   49  3   |
| 6   79  2   | 3   147 17  | 49  5   8   |
+-------------+-------------+-------------+
|79+3 36 79+6 | 4   8   37  | 5   2   1   |
|-37  1   8   | 5   67  2   | 369 39  4   |
| 2   5   4   | 16  9   136 | 36  8   7   |
+-------------+-------------+-------------+
| 8   34  67  | 67  5   9   | 34  1   2   |
| 1   346 5   | 2   36  8   | 7   34  9   |
|79+3 2   79  | 17  13  4   | 8   6   5   |
+-------------+-------------+-------------+

To avoid the DP, either R4C13 is 36, or R9C1 is 3. Either way, R5C1 is 7.

Keith
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aran



Joined: 19 Apr 2010
Posts: 70

PostPosted: Mon Oct 08, 2012 10:30 am    Post subject: Reply with quote

Or
7r4c6=(3+7)r95c1 :=><7>r4c13
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ronk



Joined: 07 May 2006
Posts: 397

PostPosted: Mon Oct 08, 2012 11:42 am    Post subject: Reply with quote

aran wrote:
Or
7r4c6=(3+7)r95c1 :=><7>r4c13

Not sure what that means but, with external DP busters only ...
(7)r4c6 = (7)r5c1 ==> r4c13<>7, stte

Using external DP busters in r4 and c1 only is sufficient because the 4th AUR cell r9c3 contains only the two UR digits.
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tlanglet



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

PostPosted: Mon Oct 08, 2012 1:39 pm    Post subject: Reply with quote

I need to seriously reviewed these posts; I sense another learning session coming on.

My non-AUR solution was a two stepper.

Finned x-wing(9)r18c12 with fin 9r1c3
[(9-6)r1c3=r1c1-(6=5=9)r78 => -9r5c1] = [x-wing(9)r18c12 => -9r5c1] => -9r5c1

xy-wing(59-8)r4c2,r1c2,r6c1 => -8r1c1,r6c2

Ted
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon Oct 08, 2012 4:01 pm    Post subject: Reply with quote

Another "simple" example for using the <79>UR. (Almost the same as Keith's solution.)

Code:
 after basics
 +-----------------------------------------------------+
 |  4    8    3    |  9    2    5    |  1    7    6    |
 |  5    79   1    |  8    467  67   |  2    49   3    |
 |  6    79   2    |  3    147  17   |  49   5    8    |
 |-----------------+-----------------+-----------------|
 | *79+3 36  *79+6 |  4    8    37   |  5    2    1    |
 |  7-3  1    8    |  5    67   2    |  369  39   4    |
 |  2    5    4    |  16   9    136  |  36   8    7    |
 |-----------------+-----------------+-----------------|
 |  8    34   67   |  67   5    9    |  34   1    2    |
 |  1    346  5    |  2    36   8    |  7    34   9    |
 | *79+3 2   *79   |  17   13   4    |  8    6    5    |
 +-----------------------------------------------------+
 # 38 eliminations remain

(3)r49c1            - (3)r5c2
(6)r4c3 - (6=3)r4c2 - (3)r5c2
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keith



Joined: 19 Sep 2005
Posts: 3179
Location: near Detroit, Michigan, USA

PostPosted: Mon Oct 08, 2012 5:14 pm    Post subject: Reply with quote

daj95376 wrote:
(Almost the same as Keith's solution.)


Yes, I didn't post it for a day because I thought it was very similar to others. Then, I saw we were slicing and dicing this every way possible.

A variant is that the 36 pair in R4 and the 3 in R9C1 respectively cause R4C6 and R5C1 to be pincers on 7.

Keith
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon Oct 08, 2012 7:59 pm    Post subject: Reply with quote

keith wrote:
Then, I saw we were slicing and dicing this every way possible.

The same reason for my post.
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