this puzzle is weird to me..

Post the puzzle or solving technique that's causing you trouble and someone will help

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Postby sarker306 » Sun Mar 08, 2009 8:11 pm

This puzzle is teasing me
8..15...3.5.8..14..91..68.5.3861259..1.....82.79....1....3..45114.5.7..8.85.417..
Why? It has no solution. I found it on sudopedia webpage for doubly linked ALS XZ example. Sorry i m using a cellphone so i can't paste the puzzle here. Hope some1 wud check what's wrong.
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From sudopedia

Postby sarker306 » Sun Mar 08, 2009 8:22 pm

This puzzle is teasing me
2.3...6.99...5...3.1.....5...........6.8.7.9.5.......4.9.....7.62..4..351...9...8
it was the one trick pony of sudocue.net on 02.28.2009. What is the trick and when n where to apply? Funny i m asking such questions but i m not so advanced....
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Re: From sudopedia

Postby daj95376 » Sun Mar 08, 2009 8:49 pm

sarker306 wrote:This puzzle is teasing me
8..15...3.5.8..14..91..68.5.3861259..1.....82.79....1....3..45114.5.7..8.85.417..
Why? It has no solution. I found it on sudopedia webpage for doubly linked ALS XZ example. Sorry i m using a cellphone so i can't paste the puzzle here. Hope some1 wud check what's wrong.

You are correct. Whoever placed this example in Sudopedia made a mistake.

Code: Select all
 +--------------------------------------------------------------+
 |  8     67    2467  |  1     5     49    |  269   267   3     |
 |  2367  5     2367  |  8     2379  39    |  1     4     69    |
 |  2347  9     1     |  247   237   6     |  8     27    5     |
 |--------------------+--------------------+--------------------|
 |  47    3     8     |  6     1     2     |  5     9     47    |
 |  4567  1     467   |  479   379   3459  |  36    8     2     |
 |  56    7     9     |  47    38    358   |  36    1     47    |
 |--------------------+--------------------+--------------------|
 |  2679  67    267   |  3     2689  89    |  4     5     1     |
 |  1     4     236   |  5     269   7     |  2369  236   8     |
 |  2369  8     5     |  29    4     1     |  7     236   69    |
 +--------------------------------------------------------------+
 # 76 eliminations remain

 *** Invalid Grid:  [b4]~2

[r6c2]=7 appears to be where the error occurred. Try [r6c2]=2.
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Re: From sudopedia

Postby hobiwan » Mon Mar 09, 2009 12:00 am

sarker306 wrote:This puzzle is teasing me
2.3...6.99...5...3.1.....5...........6.8.7.9.5.......4.9.....7.62..4..351...9...8
it was the one trick pony of sudocue.net on 02.28.2009. What is the trick and when n where to apply? Funny i m asking such questions but i m not so advanced....

If you don't want to ressort to chains I think you will need an X-Wing on candidate 4. After that a W-Wing (look for two cells containing candidates {1,2}) solves the puzzle.

Another possibility is the same X-Wing on 4, after that an X-Wing on 7 and a 2-String-Kite on 2.
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Postby daj95376 » Mon Mar 09, 2009 12:45 am

Hobiwan: I believe sarker306 is asking what one step will crack this PM to singles; i.e., the one trick pony.

Code: Select all
 *--------------------------------------------------------------------*
 | 2      5      3      | 14     7      8      | 6      14     9      |
 | 9      478    467    | 1246   5      246    | 12478  124    3      |
 | 78     1      467    | 39     26     39     | 2478   5      27     |
 |----------------------+----------------------+----------------------|
 | 78     378    9      | 45     12     45     | 1237   126    1267   |
 | 4      6      12     | 8      3      7      | 5      9      12     |
 | 5      37     12     | 269    126    269    | 37     8      4      |
 |----------------------+----------------------+----------------------|
 | 3      9      45     | 256    8      256    | 124    7      126    |
 | 6      2      8      | 7      4      1      | 9      3      5      |
 | 1      47     457    | 2356   9      2356   | 24     246    8      |
 *--------------------------------------------------------------------*
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Postby hobiwan » Mon Mar 09, 2009 2:19 am

daj95376 wrote:Hobiwan: I believe sarker306 is asking what one step will crack this PM to singles; i.e., the one trick pony

I thought so I just wasn't able to find it:D
I am not sure whether X-Wings count as advanced steps or not.
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Re: From sudopedia

Postby Luke » Mon Mar 09, 2009 5:38 am

hobiwan wrote:
sarker306 wrote:This puzzle is teasing me
2.3...6.99...5...3.1.....5...........6.8.7.9.5.......4.9.....7.62..4..351...9...8
it was the one trick pony of sudocue.net on 02.28.2009. What is the trick and when n where to apply? Funny i m asking such questions but i m not so advanced....

If you don't want to ressort to chains I think you will need an X-Wing on candidate 4. After that a W-Wing (look for two cells containing candidates {1,2}) solves the puzzle.

Another possibility is the same X-Wing on 4, after that an X-Wing on 7 and a 2-String-Kite on 2.

I think you're good. An X-wing is a simple technique by the criteria of SSTS. In fact, the puzzle solves with SSTS, so it's hard to know what to define as the equestrian move.
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Postby daj95376 » Mon Mar 09, 2009 10:02 am

hobiwan wrote:
daj95376 wrote:Hobiwan: I believe sarker306 is asking what one step will crack this PM to singles; i.e., the one trick pony

I thought so I just wasn't able to find it:D
I am not sure whether X-Wings count as advanced steps or not.

I stand corrected. The X-Wing is allowed under this constraint for a One Trick Pony.

SudoCue wrote:All but one solving steps are limited to singles, locked candidates, subsets, basic fish, UR 1 and BUG.

That said, then the PM is further reduced to ...

Code: Select all
 *-----------------------------------------------------------*
 | 2     5     3     | 14    7     8     | 6     14    9     |
 | 9     478   67    | 1246  5     246   | 178   124   3     |
 | 78    1     46    | 39    26    39    | 48    5     27    |
 |-------------------+-------------------+-------------------|
 | 78    38    9     | 45    12    45    | 13    126   1267  |
 | 4     6     12    | 8     3     7     | 5     9     12    |
 | 5     37    12    | 269   126   269   | 37    8     4     |
 |-------------------+-------------------+-------------------|
 | 3     9     45    | 256   8     256   | 14    7     16    |
 | 6     2     8     | 7     4     1     | 9     3     5     |
 | 1     47    57    | 356   9     356   | 2     46    8     |
 *-----------------------------------------------------------*

... and it has a trivial final step before Singles.
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Postby sarker306 » Thu Mar 19, 2009 12:02 pm

This is a nightmare.
.....31.42.61......1.7......2....9...754.682...9....6......4.5......23.95.38.....
I solved it using a forcenet to show r2c7=5, xwing on 1, color on 3, naked quad in r4 and forcechain to show r4c8<>4.
But i want somewhat simple technique. Did i miss sth?
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Postby daj95376 » Thu Mar 19, 2009 1:28 pm

sarker306 wrote:This is a nightmare.
.....31.42.61......1.7......2....9...754.682...9....6......4.5......23.95.38.....
I solved it using a forcenet to show r2c7=5, xwing on 1, color on 3, naked quad in r4 and forcechain to show r4c8<>4.
But i want somewhat simple technique. Did i miss sth?

You didn't mention Hidden Pair, XYZ-Wing, or UR Type 1.

Code: Select all
 r1      Naked  Triple                   <> 789  [r1c245]
 r1  b2  Naked  Pair                     <> 26   [r3c5]
 r8  b7  Locked Candidate 1              <> 4    [r8c8]
 r1  b1  Locked Candidate 1              <> 7    [r1c8]
 r3  b3  Hidden Pair                     =  26   [r3c79]
 r2  b3  Locked Candidate 1              <> 5    [r2c56]
 r57     X-Wing                          <> 1    [r68c1],[r469c9]
 r6  b5  Locked Candidate 2              <> 1    [r4c56]
 r4      Naked  Quad                     <> 3578 [r4c38]
   c9b6  Locked Candidate 1              <> 3    [r2c9]
 r6  b4  Locked Candidate 1              <> 8    [r6c56]
         XYZ-Wing [r9c9]/[r3c9]+[r7c7]   <> 6    [r7c9]
   c9    Hidden Pair                     =  26   [r39c9]
         UR Type 1 [r39c79]              <> 26   [r9c7]
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Postby hobiwan » Thu Mar 19, 2009 1:51 pm

Or UR Type 3:

Code: Select all
   Singles
   Locked Candidates Type 1 (Pointing): 7 in b1 => r1c8<>7
   Locked Candidates Type 1 (Pointing): 2 in b3 => r3c5<>2
   Locked Candidates Type 1 (Pointing): 6 in b3 => r3c5<>6
   Naked Triple: 7,8,9 in r1c138 => r1c25<>8, r1c24<>9
   Singles
   Locked Candidates Type 1 (Pointing): 4 in b7 => r8c8<>4
   Hidden Pair: 2,6 in r3c79 => r3c79<>5, r3c9<>3, r3c9<>8
   Locked Candidates Type 1 (Pointing): 5 in b3 => r2c56<>5
   X-Wing: 1 r57 c19 => r469c9,r68c1<>1
   Locked Candidates Type 2 (Claiming): 1 in r6 => r4c56<>1
   Hidden Pair: 1,4 in r4c38 => r4c3<>8, r4c8<>3, r4c8<>7
   Locked Candidates Type 1 (Pointing): 8 in b4 => r6c56<>8
   Locked Candidates Type 1 (Pointing): 3 in b6 => r2c9<>3
   .-----------------.-----------------.--------------------.
   | 789   5    78   | 26    26    3   |  1     89     4    |
   | 2     348  6    | 1     48    89  |  57    3789   578  |
   | 3489  1    48   | 7     458   589 | *26    389   *26   |
   :-----------------+-----------------+--------------------:
   | 6     2    14   | 35    578   578 |  9     14     357  |
   | 13    7    5    | 4     9     6   |  8     2      13   |
   | 348   348  9    | 235   1257  157 |  457   6      357  |
   :-----------------+-----------------+--------------------:
   | 178   68   2    | 9     3     4   |  67    5      1678 |
   | 478   468  1478 | 56    1567  2   |  3     178    9    |
   | 5     9    3    | 8    -16-7  17  | *2467  147   *267  |
   '-----------------'-----------------'--------------------'
   Uniqueness Test 3: 2/6 in r3c79,r9c79 => r9c5<>1, r9c5<>7
   Singles
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Postby eleven » Thu Mar 19, 2009 9:12 pm

sarker306 wrote:This is a nightmare
Its nice without pencilmarks. After singles and the hidden pair 26 in row 1 (see below) you are here:
Code: Select all
+-------+-------+-------+
| . 5 . | . . 3 | 1 . 4 |
| 2 . 6 | 1 . . | . . . |
| . 1 . | 7 . . | x . x |
+-------+-------+-------+
| 6 2 . | . . . | 9 . . |
| . 7 5 | 4 9 6 | 8 2 . |
| . . 9 | . . . | . 6 . |
+-------+-------+-------+
| . . 2 | 9 3 4 | . 5 . |
| . . . | . . 2 | 3 . 9 |
| 5 9 3 | 8 . . | x . x |
+-------+-------+-------+

Note the 2 and 6 in row 2 and column 8, which give you a hidden pair 26 in r1c45 and r3c79.
To avoid a deadly pattern 26 in r39c79 you need a 2 or 6 elsewhere in row 9. The only possibility is a 6 in r9c5.
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Postby sarker306 » Wed Apr 08, 2009 9:26 am

Code: Select all
.------------------.------------------.------------------.
| 18    3     2    | 4     5     9    | 7     6     18   |
| 89    4     5    | 6     7     1    | 3     29    289  |
| 179   179   6    | 28    3     28   | 4     5     19   |
:------------------+------------------+------------------:
| 157   1578  4    | 389   2     358  | 89    79    6    |
| 256   258   9    | 7     1     4568 | 28    24    3    |
| 267   278   3    | 89    4689  468  | 1     2479  5    |
:------------------+------------------+------------------:
| 259   259   1    | 239   49    234  | 6     8     7    |
| 3     269   8    | 5     69    7    | 29    1     4    |
| 4     269   7    | 1     689   268  | 5     3     29   |
'------------------'------------------'------------------'

This is the sudoku I am now working on. If i disable 3d medusa in sudocue, it offers me a tabling.
I wish some1 will help me find out some loops or chains or even easier to locate patterns.
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Postby daj95376 » Wed Apr 08, 2009 11:37 am

You need to find easier puzzles!

Code: Select all
 +--------------------------------------------------------------+
 |  18    3     2     |  4     5     9     |  7     6     18    |
 |  89    4     5     |  6     7     1     |  3     29    289   |
 |  179   179   6     |  28    3     28    |  4     5     19    |
 |--------------------+--------------------+--------------------|
 |  157   1578  4     |  389   2     358   |  89    79    6     |
 |  256   258   9     |  7     1     4568  |  28    24    3     |
 |  267   278   3     |  89    4689  468   |  1     2479  5     |
 |--------------------+--------------------+--------------------|
 |  259   259   1     |  239   49    234   |  6     8     7     |
 |  3     269   8     |  5     69    7     |  29    1     4     |
 |  4     269   7     |  1     689   268   |  5     3     29    |
 +--------------------------------------------------------------+
 # 66 eliminations remain

Code: Select all
(6)r9c2=(6-2)r8c2=(2-9)r8c7=(9)r9c9                                   => [r9c2]<>9

(1)r4c2=(1)r3c2-(1=9)r3c9-(9)r9c9=(9)r8c7-(9=8)r4c7                   => [r4c2]<>8

(8)r6c2=(8)r5c2-(8=2)r5c7-(2=9)r8c7-(9)r9c9=(9-8)r9c5=(8)r6c5-(8)r6c2 => [r5c6],[r6c46]<>8

(2)r8c2=(2)r8c7-(2=8)r4c7-(8)r5c2=(8)r6c2                             => [r6c2]<>2

(7)r6c8=(7-9)r4c8=(9-8)r4c7=(8)r5c7-(8)r5c2=(8)r6c2                   => [r6c2]<>7
__________________________________________________________________________________________

Note: The third entry is a continuous AIC loop.

ronk: Sorry, but my thoughts have switched from NL notation to Eureka/AIC/??? notation anymore.
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Postby ronk » Wed Apr 08, 2009 1:48 pm

daj95376 wrote:(8)r6c2=(8)r5c2-(8=2)r5c7-(2=9)r8c7-(9)r9c9=(9-8)r9c5=(8)r6c5-(8)r6c2 => [r5c6],[r6c46]<>8

Note: The third entry is a continuous AIC loop.

ronk: Sorry, but my thoughts have switched from NL notation to Eureka/AIC/??? notation anymore.

Why anyone would want to clutter the notation -- parentheses, often writing the same candidate twice, and writing the same cell twice for AHSs -- is beyond me. BTW in AIC notation it's 'loop' not 'continuous loop', and it's frequently written as ...

(8)r6c2=(8)r5c2-(8=2)r5c7-(2=9)r8c7-(9)r9c9=(9-8)r9c5=(8)r6c5-loop => [r5c6],[r6c46]<>8

I see you're hanging on to those square brackets for the eliminations though.:) Cool:!:
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