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		| ravel 
 
 
 Joined: 21 Apr 2006
 Posts: 536
 
 
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				|  Posted: Tue Dec 04, 2007 2:30 pm    Post subject: One from Patterns Game |   |  
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				| This puzzle by TTHsieh from the current patterns game is very nice to solve (easier than yesterday's). 
  	  | Code: |  	  | 1 . . | . . . | . . 2 . 2 . | 3 . . | . 4 .
 . . 5 | . . . | 1 . .
 - - - + - - - + - - -
 . 6 . | . 7 . | . . .
 . . . | 4 8 9 | . . .
 . . . | . 1 . | . 5 .
 - - - + - - - + - - -
 . . 1 | . . . | 7 . .
 . 4 . | . . 6 | . 2 .
 7 . . | . . . | . . 8
 
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		| Johan 
 
 
 Joined: 25 Jun 2007
 Posts: 206
 Location: Bornem  Belgium
 
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				|  Posted: Tue Dec 04, 2007 7:58 pm    Post subject: |   |  
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				| I found a contradiction in Box 1 when R1C5=4 
 R1C5=4 => R2C5=6, then we have a potential [89] DP in R28C13, which
 
 means for avoiding the DP R8C1=3 or R8C3=3, but when R8C1=3 we
 
 have a [49] DP in R46C19, and if R8C3=3 it ends up with two <9>'s in
 
 Box 1 => R1C5 <>4, breaking the puzzle wide open.
 
 
  	  | Code: |  	  | +--------------------------+--------------------------+-------------------------+
 | 1         379      349   | 5        469        478  | 369       389       2   |
 | 689       2        89    | 3        69         1    | 5         4         7   |
 | 3469      379      5     | 89       2          478  | 1         389       36  |
 +--------------------------+--------------------------+-------------------------+
 | 349       6        349   | 2        7          5    | 8         1         49  |
 | 5         1        2     | 4        8          9    | 36        7         36  |
 | 49        8        7     | 6        1          3    | 2         5         49  |
 +--------------------------+--------------------------+-------------------------+
 | 2         39       1     | 89       349        48   | 7         6         5   |
 | 389       4        389   | 7        5          6    | 39        2         1   |
 | 7         5        6     | 1        39         2    | 4         39        8   |
 +--------------------------+--------------------------+-------------------------+
 
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		| ravel 
 
 
 Joined: 21 Apr 2006
 Posts: 536
 
 
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				|  Posted: Tue Dec 04, 2007 10:06 pm    Post subject: |   |  
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				| Wow, this is a Carcul like solution. Using the 2 DP's is interesting. What is your reasoning for ? I only see 	  | Quote: |  	  | if R8C3=3 it ends up with two <9>'s in Box 1 | 
 r1c5=4 => r79c5=39 => r2c5=6 => r2c13=89
 (r1c5=4 and r8c3=9) => r1c3=9
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		| storm_norm 
 
 
 Joined: 18 Oct 2007
 Posts: 1741
 
 
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				|  Posted: Tue Dec 04, 2007 10:15 pm    Post subject: |   |  
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				| johan, 
 that is nice !!!
 
 I just spent 30 mins getting to the UR through naked pairs, pointing pairs, etc.
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		| Johan 
 
 
 Joined: 25 Jun 2007
 Posts: 206
 Location: Bornem  Belgium
 
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				|  Posted: Tue Dec 04, 2007 10:47 pm    Post subject: |   |  
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				|  	  | Quote: |  	  | if R8C3=3 it ends up with two <9>'s in Box 1 | 
 
 Ravel,
 
 When R1C5=4, you have a naked [89] pair in R2C13, then R8C3 must be
 
 <3> , for avoiding the [49] DP, leaving a single <9> in R1C3, but <9>
 
 already exists in R2C13.
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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Tue Dec 04, 2007 11:05 pm    Post subject: Pattern's game |   |  
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				| The 9's in boxes 1-3 can be cleaned up with coloring.  Then an xy-chain from R1C3 to R7C2 eliminates the 3 in R1C2 and solves the puzzle. 
 Earl
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		| ravel 
 
 
 Joined: 21 Apr 2006
 Posts: 536
 
 
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				|  Posted: Wed Dec 05, 2007 11:11 am    Post subject: |   |  
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				| Johan, 
 thats what i saw, of course my first line above can be shortened to
 r1c5=4 => r2c5=6 => r2c13=89.
 
 Earl,
 
 suppose you meant 2 kites for the 9 and an x-wing. The UR and a w-wing  also  solve it then.
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		| re'born 
 
 
 Joined: 28 Oct 2007
 Posts: 80
 
 
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				|  Posted: Wed Dec 05, 2007 11:20 am    Post subject: |   |  
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				| After basics and a UR single, we get to: 
  	  | Code: |  	  | .---------------.---------------.---------------. | 1    379  349 | 5    469  478 | 369  389  2   |
 | 689  2    89  | 3    69   1   | 5    4    7   |
 | 469  379  5   | 89   2    478 | 1    389  36  |
 :---------------+---------------+---------------:
 | 3    6    49  | 2    7    5   | 8    1    49  |
 | 5    1    2   | 4    8    9   | 36   7    36  |
 | 49   8    7   | 6    1    3   | 2    5    49  |
 :---------------+---------------+---------------:
 | 2    39   1   | 89   349  48  | 7    6    5   |
 | 89   4    389 | 7    5    6   | 39   2    1   |
 | 7    5    6   | 1    39   2   | 4    39   8   |
 '---------------'---------------'---------------'
 | 
 There is a useless xyz-wing with pivot r8c3 and pincers in r2c3 and r7c2. We conclude one of these three cells is a 9. We now transport the 9's in c3 to the (4)r4c3 and (9)r7c2 is transported to (4)r3c1 via:
 (9)r7c2 - (9=8)r7c4 - (8=4)r7c6 - (4)r3c6 = (4)r3c1.
 Now any cell that sees r4c3 and r3c1 cannot contain a 4. Hence, r6c1<>4, solving the puzzle.
 
 In Kraken notation:
 (9)r7c2 - (9=8)r7c4 - (8=4)r7c6 - (4)r3c6 = (4)r3c1
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 (9)r8c3 - (9=4)r4c3
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 (9)r2c3 - (9=4)r4c3
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		| ravel 
 
 
 Joined: 21 Apr 2006
 Posts: 536
 
 
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				|  Posted: Wed Dec 05, 2007 1:32 pm    Post subject: |   |  
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				| I guess i know, how Johan will solve the next one with this pattern   
  	  | Code: |  	  | +-------+-------+-------+ | 1 . . | . . . | . . 2 |
 | . 3 . | 1 . . | . 4 . |
 | . . 5 | . . . | 6 . . |
 +-------+-------+-------+
 | . 4 . | . 7 . | . . . |
 | . . . | 3 2 6 | . . . |
 | . . . | . 5 . | . 1 . |
 +-------+-------+-------+
 | . . 7 | . . . | 2 . . |
 | . 1 . | . . 4 | . 8 . |
 | 6 . . | . . . | . . 7 |
 +-------+-------+-------+
 
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		| nataraj 
 
 
 Joined: 03 Aug 2007
 Posts: 1048
 Location: near Vienna, Austria
 
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				|  Posted: Wed Dec 05, 2007 1:40 pm    Post subject: |   |  
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				| uh oh. we're going to have replies to two different puzzles ...
 
 "I have a bad feeling about this" (The Star Wars films)
 
 "In box 3, the ER in <2>..."
 -
 "You moron, there's no ER in box 3. You mean the skyscraper on 5" ...
 
 I love this ....
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		| nataraj 
 
 
 Joined: 03 Aug 2007
 Posts: 1048
 Location: near Vienna, Austria
 
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				|  Posted: Wed Dec 05, 2007 2:03 pm    Post subject: |   |  
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				| Don't know what Johan is going to say. Probably my contribution is also easy to predict:
 
 Medusa coloring on 7 in this position:
 
  	  | Code: |  	  | +--------------------------+--------------------------+--------------------------+
 | 1       789     89       | 6       4       5        | 38      37      2        |
 | 78      3       6        | 1       9       2        | 578     4       58       |
 | 4       2       5        | 8       3       7        | 6       9       1        |
 +--------------------------+--------------------------+--------------------------+
 | 358     4       38       | 9       7       1        | 358     2       6        |
 | 89      57      1        | 3       2       6        | 4       57      89       |
 | 279     6       239      | 4       5       8        | 379     1       39       |
 +--------------------------+--------------------------+--------------------------+
 | 389     89      7        | 5       1       39       | 2       6       4        |
 | 235     1       23       | 7       6       4        | 359     8       359      |
 | 6       59      4        | 2       8       39       | 1       35      7        |
 +--------------------------+--------------------------+--------------------------+
 
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 ... just because I've never seen a plot like this in sudoku:
 
  	  | Code: |  	  | +·····+·····+·····+
 ·  *-----------*  ·
 · /|  ·     · /|  ·
 ·*-----------* |  ·
 ·| |  ·     ·| |  ·
 ·| |  ·     ·| |  ·
 +|·|··+·····+|·|··+
 ·| |  ·     ·| |  ·
 ·| |  ·     ·| |  ·
 ·| *-----------*  ·
 ·|/   ·     ·|/   ·
 ·*-----------*    ·
 +·····+·····+·····+
 ·     ·     ·     ·
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 If you look closely ...
 
   
 if red is true, there can be no "2" in column 1. Thus red is false and the puzzle is solved ...
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		| Johan 
 
 
 Joined: 25 Jun 2007
 Posts: 206
 Location: Bornem  Belgium
 
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				|  Posted: Wed Dec 05, 2007 2:54 pm    Post subject: |   |  
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				| I used the same strategy as the previous one, this time a contradiction in 
 Box 9.
 
 If R8C1=5, we have a potential [39] DP in R68C79, the only solution for
 
 avoiding this DP is that R6C7 must be <7> => R5C8=5 => R9C8=3, now
 
 we hava a contradiction in Box 9, because <3> already exists in R8C79
 
 => R8C1<>5.
 
 
  	  | Code: |  	  | +--------------------------+--------------------------+-------------------------+
 | 1         789       89   | 6           4        5   | 378        37      2    |
 | 78        3         6    | 1           9        2   | 578        4       58   |
 | 4         2         5    | 8           3        7   | 6          9       1    |
 +--------------------------+--------------------------+-------------------------+
 | 358       4         38   | 9           7        1   | 358        2       6    |
 | 5789      5789      1    | 3           2        6   | 4          57      589  |
 | 2379      6         239  | 4           5        8   | 379        1       39   |
 +--------------------------+--------------------------+-------------------------+
 | 389       89        7    | 5           1        39  | 2          6       4    |
 | 235       1         23   | 7           6        4   | 359        8       359  |
 | 6         59        4    | 2           8        39  | 1          35      7    |
 +--------------------------+--------------------------+-------------------------+
 
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		| ravel 
 
 
 Joined: 21 Apr 2006
 Posts: 536
 
 
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				|  Posted: Wed Dec 05, 2007 4:10 pm    Post subject: |   |  
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				| Bingo, i knew, you would spot that   In other words: To avoid the 39-DP either r8c7=5, r8c9=5 or (r6c7=7 =>) r5c8=5. Since r9c8 sees all 3 cells, it cant be 5.
 
 
 Sorry, should have made a new thread 	  | nataraj wrote: |  	  | uh oh. we're going to have replies to two different puzzles ...
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		| nataraj 
 
 
 Joined: 03 Aug 2007
 Posts: 1048
 Location: near Vienna, Austria
 
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				|  Posted: Wed Dec 05, 2007 4:21 pm    Post subject: |   |  
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				|  	  | ravel wrote: |  	  | Sorry, should have made a new thread  | 
 nah, NP. didn't think there really would be trouble. Only my imagination running wild
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