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		| keith 
 
 
 Joined: 19 Sep 2005
 Posts: 3355
 Location: near Detroit, Michigan, USA
 
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				|  Posted: Thu Mar 28, 2013 5:55 am    Post subject: Impossible Menneske No. 11 |   |  
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				|  	  | Code: |  	  | M6911767  Impossible (4692) +-------+-------+-------+
 | . . . | . 4 . | . . . |
 | . . 4 | . . 1 | . 9 . |
 | . . . | 7 . . | 6 8 . |
 +-------+-------+-------+
 | . 8 . | 5 . . | . . . |
 | . 9 . | . . . | . 4 . |
 | . 6 . | . . 9 | . 3 . |
 +-------+-------+-------+
 | . 1 . | . . 3 | . . 7 |
 | . . . | . . . | 9 . . |
 | 6 . . | . 8 2 | . . . |
 +-------+-------+-------+
 
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 Play this puzzle online at the Daily Sudoku site
 
 By the way, please note that I do not filter these puzzles in any way.  They come from the Menneske site, based only on the rating of "Impossible".  http://www.menneske.no/sudoku/eng/
 
 Keith
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		| JC Van Hay 
 
 
 Joined: 13 Jun 2010
 Posts: 494
 Location: Charleroi, Belgium
 
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				|  Posted: Thu Mar 28, 2013 8:27 am    Post subject: |   |  
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				| #1. UP27 Hidden Singles : r3c9=4, r3c3=6, r4c9=9
 Naked Single : r3c6=5, r1c6=8
 Hidden Single : r2c1=8
 
 LC(1) :=> -1r1c1
 LC(4) :=> -4r78c1
 Finned XWing(6C69) :=> -6r5c45 ![Optional]
 LC(7) :=> -7r8c123
 Finned XWing(8C18) :=> -8r4c3 ![Optional]
 Skyscraper (9R19) :=> -9r3c3.r7c1 ![Only -9r3c3 required for the loop below]
 #2.
 
  	  | Code: |  	  | +---------------------------+-----------------------+-------------------------+ | -235(79)  235(7)  6       | 23(9)  4        8     | 12357    1257  1235     |
 | 8         235(7)  4       | 236    236      1     | 2357     9     235      |
 | 1239      23      123     | 7      23(9)    5     | 6        8     4        |
 +---------------------------+-----------------------+-------------------------+
 | 12347     8       123     | 5      12367    467   | 127      1267  9        |
 | 12357     9       12357   | 1238   1237     (67)  | 12578    4     1258(6)  |
 | 12457     6       1257    | 1248   127      9     | 12578    3     1258     |
 +---------------------------+-----------------------+-------------------------+
 | 25        1       25-8(9) | 46-9   6(59)    3     | 24-5(8)  256   7        |
 | 235       2345    2358    | 146    1-6(57)  46(7) | 9        1256  1235(68) |
 | 6         345(7)  -35(79) | 149    8        2     | 1345     15    135      |
 +---------------------------+-----------------------+-------------------------+
 Chain[10] : Loop{9r7c3=(9-7)r9c3=7r9c2-7r12c2=(7-9)r1c1=9r1c4-9r3c5=9r7c5}- ...
 ... -5r7c5=(5-7)r8c5=7r8c6-(7=6)r5c6-6r5c9=(6-8)r8c9=8r7c7
 
 :=> [r9c3=79, r1c1=79, -9r7c4] ![Optional]
 :=> [7r8c5=6r8c9 :=> -6r8c5], [5r7c5=8r7c7 :=> -5r7c7] ![Optional]
 :=> [9r7c3=8r7c7 :=> -8r7c3 (r7c7=8)]
 
 :=> UP34; XWing(6C69) :=> -6r8c48[+eventually -6r8c8.r5c45]; UP41
 LC(5)[+eventually LC(7)] :=> r9c2=3; UP81
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		| arkietech 
 
 
 Joined: 31 Jul 2008
 Posts: 1834
 Location: Northwest Arkansas USA
 
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				|  Posted: Thu Mar 28, 2013 6:04 pm    Post subject: |   |  
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				|  	  | Code: |  	  | *-----------------------------------------------------------------------------* | 23579   2357    6       | 239     4       8       | 12357   1257    1235    |
 | 8       2357    4       | 236     236     1       | 2357    9       235     |
 | 1239    23      1239    | 7       239     5       | 6       8       4       |
 |-------------------------+-------------------------+-------------------------|
 | 12347   8       1237    | 5       12367   467     | 127     1267    9       |
 | 12357   9       12357   | 12368   12367   67      | 12578   4       12568   |
 | 12457   6       1257    | 1248    127     9       | 12578   3       1258    |
 |-------------------------+-------------------------+-------------------------|
 | 259     1       2589    | 469     569     3       | 2458    256     7       |
 | 235     2345    2358    | 146     1567    467     | 9       1256    123568  |
 | 6       3457    3579    | 149     8       2       | 1345    15      135     |
 *-----------------------------------------------------------------------------*
 6r5c6-r4c6=(6-7)r4c8=7r1c8
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 7r5c6-r8c6=(7-5)r8c5=(5-9)r7c5=r3c5-r1c4=9r1c1
 => -7r1c1; lclste
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		| oaxen 
 
 
 Joined: 10 Jul 2006
 Posts: 96
 
 
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				|  Posted: Wed Apr 03, 2013 9:23 am    Post subject: |   |  
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				| A little bit easier than No 10. There are many bivalues and probably more ways to solve it. I found "9" in row 9 most promising and with parallell chains many digits are fixed in both cases. "9" in R9C4 is correct. |  | 
	
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		| DonM 
 
 
 Joined: 15 Sep 2009
 Posts: 51
 
 
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				|  Posted: Sun Apr 21, 2013 5:20 am    Post subject: |   |  
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				| Menneske Impossible 11 ER=7.2 post-SSTS: 
  	  | Code: |  	  | *-----------------------------------------------------------------------------*
 | 23579   2357    6       | 239     4       8       | 12357   1257    1235    |
 | 8       2357    4       | 236     236     1       | 2357    9       235     |
 | 1239    23      123     | 7       239     5       | 6       8       4       |
 |-------------------------+-------------------------+-------------------------|
 | 12347   8       1237    | 5       12367   467     | 127     1267    9       |
 | 12357   9       12357   | 12368   12367   67      | 12578   4       12568   |
 | 12457   6       1257    | 1248    127     9       | 12578   3       1258    |
 |-------------------------+-------------------------+-------------------------|
 | 25      1       2589    | 469     569     3       | 2458    256     7       |
 | 235     2345    2358    | 146     1567    467     | 9       1256    123568  |
 | 6       3457    3579    | 149     8       2       | 1345    15      135     |
 *-----------------------------------------------------------------------------*
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 (9)r3c5=(9-5)r7c5=(5-7)r8c5=r8c6-(7=6)r5c6-r5c9=(6-7)r4c8=r1c8-r2c7=r2c2-r9c2=(7-9)r9c3=(9)r9c4 => -9r1c4 -> r1c1=9
 lcste
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