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July 31 VH, with apologies to Early Earl

 
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Fri Jul 31, 2009 12:42 am    Post subject: July 31 VH, with apologies to Early Earl Reply with quote
After basics.

Code:

+----------+---------------+-----------+
| 9  36 45 | 2   68   3468 | 568 7  1  |
| 7  2  45 | 468 1    9    | 568 68 3  |
| 8  36 1  | 5   7    36   | 4   9  2  |
+----------+---------------+-----------+
| 1  4  7  | 68  3    5    | 9   2  68 |
| 6  8  3  | 9   2    1    | 7   5  4  |
| 2  5  9  | 7   4    68   | 3   1  68 |
+----------+---------------+-----------+
| 45 1  6  | 3   58   7    | 2   48 9  |
| 45 79 2  | 1   5689 468  | 568 3  57 |
| 3  79 8  | 46  59   2    | 1   46 57 |
+----------+---------------+-----------+

Play this puzzle online at the Daily Sudoku site

Quote:
In the potential DP 57-59-79 in boxes 789 the only way to kill it is with either a 6 or 8 in r8c5. This forms a 68 pair with r1c5 and that solves it.
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crunched



Joined: 05 Feb 2008
Posts: 168
PostPosted: Fri Jul 31, 2009 12:58 am    Post subject: Reply with quote
Impressive indeed, Marty.
I used the more conventional wing solutions. An xyz, followed by an xy.

Quote:
(xyz wing uses 4-6-8 followed by xy wing of 46-48-68 )
Code:

+----------+---------------+-----------+
| 9  36 45 | 2   68   3468 | 568 7  1  |
| 7  2  45 | 468 1    9    | 568 68 3  |
| 8  36 1  | 5   7    36   | 4   9  2  |
+----------+---------------+-----------+
| 1  4  7  | 68  3    5    | 9   2  68 |
| 6  8  3  | 9   2    1    | 7   5  4  |
| 2  5  9  | 7   4    68   | 3   1  68 |
+----------+---------------+-----------+
| 45 1  6  | 3   58   7    | 2   48 9  |
| 45 79 2  | 1   5689 468  | 68  3  57 |
| 3  79 8  | 46  59   2    | 1   46 57 |
+----------+---------------+-----------+

Play this puzzle online at the Daily Sudoku site

Last edited by crunched on Fri Jul 31, 2009 4:08 am; edited 1 time in total
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA
PostPosted: Fri Jul 31, 2009 1:10 am    Post subject: Reply with quote
I used two steps
Quote:
w-wing 68
w-wing 84
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rayswchiu



Joined: 31 Jul 2009
Posts: 1
PostPosted: Fri Jul 31, 2009 1:24 am    Post subject: i used remote pairs Reply with quote
68
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David



Joined: 02 Jun 2006
Posts: 58
Location: Bedford, UK
PostPosted: Fri Jul 31, 2009 2:19 pm    Post subject: Reply with quote
C'mon Earl, we all know you have stolen Marty's IP address and pretended to post under his name !

Crunched - unless I made a mistake, can you not solve the puzzle with just the 468 xyz wing ? [/quote]
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Fri Jul 31, 2009 3:42 pm    Post subject: Reply with quote
Quote:
Crunched - unless I made a mistake, can you not solve the puzzle with just the 468 xyz wing ?

I'm not Crunched...but using his grid I couldn't solve it with the XYZ-Wing. I got stuck here:

Code:

+----------+-----------+-----------+
| 9  3  45 | 2  6   48 | 58  7  1  |
| 7  2  45 | 48 1   9  | 568 68 3  |
| 8  6  1  | 5  7   3  | 4   9  2  |
+----------+-----------+-----------+
| 1  4  7  | 68 3   5  | 9   2  68 |
| 6  8  3  | 9  2   1  | 7   5  4  |
| 2  5  9  | 7  4   68 | 3   1  68 |
+----------+-----------+-----------+
| 45 1  6  | 3  58  7  | 2   48 9  |
| 45 79 2  | 1  589 46 | 68  3  57 |
| 3  79 8  | 46 59  2  | 1   46 57 |
+----------+-----------+-----------+

Play this puzzle online at the Daily Sudoku site
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Clement



Joined: 24 Apr 2006
Posts: 1111
Location: Dar es Salaam Tanzania
PostPosted: Fri Jul 31, 2009 4:15 pm    Post subject: Fri 31-Jul-2009 VH Reply with quote
I used three steps:-
1) UR (36)r13c26 eliminating 36 in r1c6.
2) XYZ-Wing (46)r9c4-(468)r8c6-(68)r8c7 eliminating 6 in r8c5 leading to
3) an XY-Wing (46)r9c8-(68)r2c8-(48)r2c4 eliminating 4 in r9c4 completes the puzzle.
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cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada
PostPosted: Fri Jul 31, 2009 5:51 pm    Post subject: Reply with quote
Looking at Clement's steps - the puzzle can be done with just the two 468 wings. Don't need no UR!
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cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada
PostPosted: Fri Jul 31, 2009 5:52 pm    Post subject: Reply with quote
Looking at Clement's steps - the puzzle can be done with just the two 468 wings. Don't need no UR!
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David



Joined: 02 Jun 2006
Posts: 58
Location: Bedford, UK
PostPosted: Fri Jul 31, 2009 5:53 pm    Post subject: Reply with quote
Marty,
If you go back to your first grid (posting), then I believe you can eliminate the 5 from R9 C7 to leave 68 (due to the 5's in box 3. Do you not then have an XYZ wing (46-468-68, boxes 8,9) that eliminates the 6 in R9 C8 ?
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Roger S



Joined: 20 Jun 2009
Posts: 6
Location: UK
PostPosted: Fri Jul 31, 2009 9:06 pm    Post subject: Reply with quote
Marty

If you go back to your origional post is there an xyz wing in 468-68-46 in
R2c4 (468) R2C8 (6Cool R9C4(46) eliminating the 6 inR9C4 I did that and it dropped out but not sure if its correct
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Wendy W



Joined: 04 Feb 2008
Posts: 144
PostPosted: Fri Jul 31, 2009 10:07 pm    Post subject: Reply with quote
This one was a welcome change from the usual no-brainers!
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Sat Aug 01, 2009 2:03 am    Post subject: Reply with quote
David wrote:
Marty,
If you go back to your first grid (posting), then I believe you can eliminate the 5 from R9 C7 to leave 68 (due to the 5's in box 3. Do you not then have an XYZ wing (46-468-68, boxes 8,9) that eliminates the 6 in R9 C8 ?

David, yes, that 5 should have been gone but the XYZ-Wing in boxes 89 eliminates the 6 from r8c5.

Quote:

If you go back to your origional post is there an xyz wing in 468-68-46 in
R2c4 (468) R2C8 (6Cool R9C4(46) eliminating the 6 inR9C4 I did that and it dropped out but not sure if its correct

Roger, that is an XYZ-Wing, but because it's in three different boxes it doesn't eliminate anything because there's no cell I can see that sees all three of XYZ, XZ and YZ.
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
PostPosted: Sat Aug 01, 2009 2:49 pm    Post subject: Reply with quote
I used two xy-wings to complete the puzzle.
xy-wing 46-8 with pivot 46 in r9c8 and pseudocell 48 in col4 plus a transport
xy-wing -458 with pivot 58 in r7c5.

Ted
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