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UR+SL: Mike Barker's UR+2B/1SL

 
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon Oct 31, 2011 8:47 pm    Post subject: UR+SL: Mike Barker's UR+2B/1SL Reply with quote

I'm only going to post one pattern for each thread in this forum. Should I get to the point of creating a thread in the Solving Techniques forum, then I'll move each head post from the threads here into messages in a single thread there.

===== ===== ===== ===== Mike Barker's UR+2B/1SL

Code:
Bivalues in [c1] and one SL in [r5]
+--------------+
|  .   .   .   |
| 12   .  1X-2 |
|  .   .   .   |
+--------------+
|  .   .   .   |
| 12   .  12Y  |<  SL on <1>
|  .   .   .   |
+--------------+

 2x SL  variant   (equivalent to UR Type 4)
+--------------+
|  .   .   .   |
| 12   .  1X-2 |<  SL on <1>
|  .   .   .   |
+--------------+
|  .   .   .   |
| 12   .  1Y-2 |<  SL on <1>
|  .   .   .   |
+--------------+

Puzzle from Mike Barker's "zoo" collection:

Code:
..3.4.8.74...21.3..1.....4..381.........7...8.4...5..29..........73........65.4..

 +--------------------------------------------------------------+
 |  26    269   3     |  5     4     69    |  8     1     7     |
 |  4     7     569   |  8     2     1     |  569   3     569   |
 |  8     1     569   |  7     3     69    |  2     4     569   |
 |--------------------+--------------------+--------------------|
 |  57    3     8     |  1     6     2     |  579   579   4     |
 |  256   2569  269   |  4     7     3     |  1     56    8     |
 |  167   4     16    |  9     8     5     |  3     67    2     |
 |--------------------+--------------------+--------------------|
 |  9     568   4     |  2     1    *78    |  567  *78+5  3     |
 |  1256  2568  7     |  3     9     4     |  56    258   156   |
 |  3     28    12    |  6     5    *78    |  4    *78+29 19    |<  SL on <7>
 +--------------------------------------------------------------+
 # 57 eliminations remain

 r79c68  <78> UR via s-link              <> 8    r7c8


I'm adding this pattern to this thread because of its similarity to the 2x variant above ... and because of ronk's comment. When an X-Wing exists in the UR cells, then there's no "essential difference" from applying the first pattern 2x times, or the following pattern once.

===== ===== ===== ===== Mike Barker's UR+2X/1SL

Code:
Bivalues in [c1] and one SL in [c3]   (aka UR Type 4)
+--------------+
|  .   .   .   |
| 12   .  1X-2 |
|  .   .   .   |
+--------------+
|  .   .   .   |
| 12   .  1Y-2 |
|  .   .   .   |
+--------------+
           ^       SL on <1>

Since examples of UR Type 4 abound, I'm not going to include an example puzzle.


Last edited by daj95376 on Tue Nov 01, 2011 5:17 am; edited 2 times in total
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ronk



Joined: 07 May 2006
Posts: 397

PostPosted: Mon Oct 31, 2011 9:40 pm    Post subject: Re: UR+SL: Mike Barker's UR+2B/1SL Reply with quote

daj95376 wrote:
Code:

 2x SL  variant   (aka UR Type 4)
+--------------+
|  .   .   .   |
| 12   .  1X-2 |<  SL on <1>
|  .   .   .   |
+--------------+
|  .   .   .   |
| 12   .  1Y-2 |<  SL on <1>
|  .   .   .   |
+--------------+

A Type 4 would have a single SL on <1> in column 3.
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon Oct 31, 2011 11:58 pm    Post subject: Reply with quote

Ron,

I've updated the head post and hope that I've addressed your point/concerns. My intent was to show that 2x applications of a particular pattern would lead to eliminations equivalent to a known UR Type.
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ronk



Joined: 07 May 2006
Posts: 397

PostPosted: Tue Nov 01, 2011 12:55 am    Post subject: Reply with quote

daj95376 wrote:
My intent was to show that 2x applications of a particular pattern would lead to eliminations equivalent to a known UR Type.

But that's quite different than "aka".
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Tue Nov 01, 2011 5:18 am    Post subject: Reply with quote

ronk wrote:
But that's quite different than "aka".

Accepted. Post updated.
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