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Free Press Apr 09, 2010

 
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Fri Apr 09, 2010 2:39 pm    Post subject: Free Press Apr 09, 2010 Reply with quote

Code:
Puzzle: FP040910
+-------+-------+-------+
| . . 6 | 8 . 3 | 5 . . |
| . 4 . | . 2 5 | . 7 . |
| 2 . . | . . . | . . . |
+-------+-------+-------+
| 9 6 . | . . . | . . 3 |
| . . 3 | 6 . 1 | 4 . . |
| 7 . . | . . . | . 1 6 |
+-------+-------+-------+
| . . . | . . . | . . 7 |
| . 3 . | 7 1 . | . 9 . |
| . . 7 | 9 . 4 | 3 . . |
+-------+-------+-------+
Keith
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Fri Apr 09, 2010 6:23 pm    Post subject: Reply with quote

After basics:
Code:
+----------------+----------------+----------------+
| 1    7    6    | 8    9    3    | 5    24   24   |
| 3    4    9    | 1    2    5    | 6    7    8    |
| 2    58   58   | 4    6    7    | 9    3    1    |
+----------------+----------------+----------------+
| 9    6    1    | 25   4    28   | 7    58   3    |
| 58   2    3    | 6    7    1    | 4    58   9    |
| 7    58   4    | 35   358  9    | 2    1    6    |
+----------------+----------------+----------------+
| 4568 9    258  | 235  358  268  | 1    46   7    |
| 456  3    25   | 7    1    26   | 8    9    45   |
| 568  1    7    | 9    58   4    | 3    26   25   |
+----------------+----------------+----------------+


Keith


Last edited by keith on Fri Apr 09, 2010 9:24 pm; edited 1 time in total
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Marty R.



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

PostPosted: Fri Apr 09, 2010 8:51 pm    Post subject: Reply with quote

I used a rather long simple coloring chain on 8 and a Type1 UR on 35.
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Fri Apr 09, 2010 9:32 pm    Post subject: Reply with quote

SS8 R69 solves R5C1 as 5.
46 W-wing solves it by removing 4 in R7C1.

Keith
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tlanglet



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

PostPosted: Fri Apr 09, 2010 11:28 pm    Post subject: Reply with quote

Two steps here also.

HP26[(26)r78c6 = (8)r7c6]r78c6 - r7c13 = r9c1 - (8=5)r5c1 - r6c2 = r6c45 - (5=2)r4c4; r4c6<>2
Type 1 UR 35 r67c45 forces r7c5=8

Ted
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Sat Apr 10, 2010 1:23 am    Post subject: Reply with quote

keith wrote:
After basics:
Code:
+----------------+----------------+----------------+
| 1    7    6    | 8    9    3    | 5    24   24   |
| 3    4    9    | 1    2    5    | 6    7    8    |
| 2    58   58   | 4    6    7    | 9    3    1    |
+----------------+----------------+----------------+
| 9    6    1    | 25   4    28   | 7    58   3    |
| 58   2    3    | 6    7    1    | 4    58   9    |
| 7    58   4    | 35   358  9    | 2    1    6    |
+----------------+----------------+----------------+
| 4568 9    258  | 235  358  268  | 1    46   7    |
| 456  3    25   | 7    1    26   | 8    9    45   |
| 568  1    7    | 9    58   4    | 3    26   25   |
+----------------+----------------+----------------+


<35> UR in r67c45 implies r67c5=8 or r7c4=2

r67c5=8 => r9c5<>8
r7c4=2, r8c6=6, r7c6=8 => r9c5<>8

Singles follow.
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Sat Apr 10, 2010 1:40 am    Post subject: Reply with quote

Danny,

That's pretty sweet, isn't it!

In the solution I posted, I decided to stay away from Uniqueness arguments. Not that there's anything wrong with that (Seinfeld). Wink Wink

Keith
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Sat Apr 10, 2010 4:55 am    Post subject: Reply with quote

keith wrote:
Danny,

That's pretty sweet, isn't it!

Yes Exclamation

It's particularly impressive because I found it myself and not my solver.

I can still recall the time I encountered your post on URs ... and I could not get the principle through my thick skull. Now, I have a solver that catches many UR patterns ... just not the one I found here.

Regards, Danny
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