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arkietech
Joined: 31 Jul 2008 Posts: 1834 Location: Northwest Arkansas USA
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Posted: Wed May 16, 2012 6:10 am Post subject: au tough 5/16/12 |
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Code: |
*-----------*
|68.|..3|9..|
|...|...|5..|
|7..|..4|..6|
|---+---+---|
|...|2..|...|
|.39|...|18.|
|...|..8|...|
|---+---+---|
|9..|7..|..3|
|..1|...|...|
|..4|6..|.79|
*-----------*
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arkietech
Joined: 31 Jul 2008 Posts: 1834 Location: Northwest Arkansas USA
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Posted: Wed May 16, 2012 7:55 pm Post subject: |
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Code: |
*--------------------------------------------------------------------*
| 6 8 25 | 15 1257 3 | 9 4 17 |
| 14 149 23 | 8 1679 67 | 5 23 17 |
| 7 19 235 | 159 1259 4 | 8 23 6 |
|----------------------+----------------------+----------------------|
| 1458 146 d678 | 2 b13459 59 |c37 69 45 |
| 245 3 9 | 45 67 67 | 1 8 245 |
| 1245 1246 67 | 13459 13459 8 | 37 69 245 |
|----------------------+----------------------+----------------------|
| 9 26 e68 | 7 5-8 25 | 4 1 3 |
| 23 7 1 | 349 349 29 | 6 5 8 |
| 3-8 5 4 | 6 a38 1 | 2 7 9 |
*--------------------------------------------------------------------*
(8=3)r9c5-r4c5=(3-7)r4c7=(7-8)r4c3=(8)r7c3 => r7c5,r9c1<>8; stte
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Wed May 16, 2012 8:51 pm Post subject: |
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I can't find chains like that. A 67 UR brought me to the below grid where a Medusa wrap easily solves it, but I didn't see a more conventional move.
Code: |
+---------------+-------------+-----------+
| 6 8 2 | 5 7 3 | 9 4 1 |
| 14 149 3 | 8 19 6 | 5 2 7 |
| 7 19 5 | 19 2 4 | 8 3 6 |
+---------------+-------------+-----------+
| 1458 146 678 | 2 1359 59 | 37 69 45 |
| 25 3 9 | 4 6 7 | 1 8 25 |
| 1245 1246 67 | 139 1359 8 | 37 69 245 |
+---------------+-------------+-----------+
| 9 26 68 | 7 58 25 | 4 1 3 |
| 23 7 1 | 39 4 29 | 6 5 8 |
| 38 5 4 | 6 38 1 | 2 7 9 |
+---------------+-------------+-----------+
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arkietech
Joined: 31 Jul 2008 Posts: 1834 Location: Northwest Arkansas USA
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Posted: Wed May 16, 2012 9:34 pm Post subject: |
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Marty R. wrote: | I can't find chains like that. |
(8=3)r9c5-r4c5=(3-7)r4c7=(7-8)r4c3=(8)r7c3 => r7c5,r9c1<>8; stte
if r9c5 is not an 8 it is a 3, making r4c7 a 3, and r4c3 a 7, This makes r7c3 an 8 => r7c5,r9c1<>8; stte
hope this helps |
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Wed May 16, 2012 9:48 pm Post subject: |
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Thanks Dan. I'm able to follow the chain OK, but I don't see the grid in a way that would lead me to these types of chains. Or maybe I just don't try hard enough. |
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tlanglet
Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
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Posted: Thu May 17, 2012 2:05 am Post subject: |
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I just got around to working on this puzzle and , like Marty, my best move to date is the UR(67). I expect/hope to pursue a good solution later......
Ted |
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tlanglet
Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
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Posted: Thu May 17, 2012 2:27 am Post subject: |
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Well, I did find a nice two step solution as follows.
Type 1 UR(67)r25c56; r2c5<>67
This results in a grid:
Code: | *-----------------------------------------------------------*
| 6 8 2 | 5 7 3 | 9 4 1 |
| 14 149 3 | 8 19 6 | 5 2 7 |
| 7 19 5 | 19 2 4 | 8 3 6 |
|-------------------+-------------------+-------------------|
| 1458 146 678 | 2 1359 59 | 37 69 45 |
| 25 3 9 | 4 6 7 | 1 8 25 |
| 1245 1246 67 | 139 1359 8 | 37 69 245 |
|-------------------+-------------------+-------------------|
| 9 26 68 | 7 58 25 | 4 1 3 |
| 23 7 1 | 39 4 29 | 6 5 8 |
| 38 5 4 | 6 38 1 | 2 7 9 |
*-----------------------------------------------------------*
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(3=9)r8c4-(19=3)r36c4-(3=7)r6c7-(7=6)r6c3-(6=8)r7c3-(8=3)r9c1; r8c1<>3
Ted |
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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Thu May 17, 2012 2:37 am Post subject: |
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Ted, do you find anything interesting about cells r12c59? Later, there's r26c12! None of this cracks the puzzle, but it does make for an interesting combination of steps before you need something more advanced -- like a chain. |
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tlanglet
Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
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Posted: Thu May 17, 2012 12:26 pm Post subject: |
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daj95376 wrote: | Ted, do you find anything interesting about cells r12c59? Later, there's r26c12! None of this cracks the puzzle, but it does make for an interesting combination of steps before you need something more advanced -- like a chain. |
Danny,
Not sure if I am picking up on the point you are noting, but this puzzle has lots of potential deadly patterns. I was able to get some deletions from several but never any of significance. The one I really liked was the "Is it a MUG?" pattern (3679)r46c3578.
AMUG(3679)r46c3578 SIS (3)r6c4, (6)r7c3, (9)r2c5; r2c5=9
(3-1)r6c4=r3c4-(1=9)r2c5;
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(6)r7c3-(6=2)r7c2-(2=3)r8c1-r8c4=(3-1)r6c4=r3c4-(1=9)r2c5;
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(9)r2c5;
Ted |
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Luke451
Joined: 20 Apr 2008 Posts: 310 Location: Southern Northern California
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Posted: Thu May 17, 2012 11:34 pm Post subject: |
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tlanglet wrote: | "Is it a MUG?" |
I assume this is the position at the DP.
Code: | *-----------------------------------------------------------*
| 6 8 2 | 5 7 3 | 9 4 1 |
| 14 149 3 | 8 19 6 | 5 2 7 |
| 7 19 5 | 19 2 4 | 8 3 6 |
|-------------------+-------------------+-------------------|
| 1458 146 *67+8 | 2 *39+15 59 |*37 *69 45 |
| 25 3 9 | 4 6 7 | 1 8 25 |
| 1245 1246 *67 | 139 *39+15 8 |*37 *69 245 |
|-------------------+-------------------+-------------------|
| 9 26 68 | 7 58 25 | 4 1 3 |
| 23 7 1 | 39 4 29 | 6 5 8 |
| 38 5 4 | 6 38 1 | 2 7 9 |
*-----------------------------------------------------------* |
I think the pattern may be a BUG-Lite rather than a MUG. You are the master of the "external out!" |
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aran
Joined: 19 Apr 2010 Posts: 70
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Posted: Sun May 20, 2012 12:50 pm Post subject: |
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Luke451 wrote: | tlanglet wrote: | "Is it a MUG?" |
I assume this is the position at the DP.
Code: | *-----------------------------------------------------------*
| 6 8 2 | 5 7 3 | 9 4 1 |
| 14 149 3 | 8 19 6 | 5 2 7 |
| 7 19 5 | 19 2 4 | 8 3 6 |
|-------------------+-------------------+-------------------|
| 1458 146 *67+8 | 2 *39+15 59 |*37 *69 45 |
| 25 3 9 | 4 6 7 | 1 8 25 |
| 1245 1246 *67 | 139 *39+15 8 |*37 *69 245 |
|-------------------+-------------------+-------------------|
| 9 26 68 | 7 58 25 | 4 1 3 |
| 23 7 1 | 39 4 29 | 6 5 8 |
| 38 5 4 | 6 38 1 | 2 7 9 |
*-----------------------------------------------------------* |
I think the pattern may be a BUG-Lite rather than a MUG. You are the master of the "external out!" |
A propos of recent discussions : just to note the corresponding 9-N pattern : 12458r46c12469, with its avoidance candidates 6r46c2, 39r6c4 9r4c6 (all pointing to r3c4=1).
Obviously no solving advantage over the BUG-lite, so the point is just to observe it.
daj drew attention to r12c59. ie to the fact that the solved cells contain no givens, so this is UR territory =>r2c5=9 |
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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Sun May 20, 2012 1:31 pm Post subject: |
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aran wrote: | daj drew attention to r12c59. ie to the fact that the solved cells contain no givens, so this is UR territory =>r2c5=9 |
Yes ... and ... it exposes a 14UR Type 3. Unfortunately, it still doesn't crack the puzzle, but it does allow a simpler chain to crack it. |
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