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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Thu Jun 02, 2011 10:00 pm Post subject: Puzzle 11/06/02: ~ XY (BBDB) |
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Code: | +-----------------------+
| . 2 . | 7 1 . | 8 5 . |
| 5 8 7 | . 2 . | . . 3 |
| . 3 6 | . . 8 | 2 7 . |
|-------+-------+-------|
| 2 . . | 6 . . | . . . |
| 6 7 . | . 4 . | . . 8 |
| . . 8 | . . 2 | 6 . . |
|-------+-------+-------|
| 7 . 2 | . . 1 | . . . |
| 3 . 1 | . . . | . 8 . |
| . 5 . | . 6 . | . . 2 |
+-----------------------+
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Play this puzzle online at the Daily Sudoku site |
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tlanglet
Joined: 17 Oct 2007 Posts: 2468 Location: Northern California Foothills
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Posted: Fri Jun 03, 2011 2:29 pm Post subject: |
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Not sure how to notate this one step solution involving an "almost" AIC.
Code: | *--------------------------------------------------------------------*
| 49 2 49 | 7 1 3 | 8 5 6 |
| 5 8 7 | 49 2 6 | 149 149 3 |
| 1 3 6 | 459 59 8 | 2 7 49 |
|----------------------+----------------------+----------------------|
| 2 49 35 | 6 8 579 | 34579 349 1 |
| 6 7 35 | 1 4 59 | 359 2 8 |
| 49 1 8 | 35 357 2 | 6 49 57 |
|----------------------+----------------------+----------------------|
| 7 49 2 | 8 359 1 | 3459 6 (45)9 |
| 3 6 1 | 2 579 457 | 4579 8 4579 |
| 8 5 49 | 39 6 47 | 13479 1349 2 |
*--------------------------------------------------------------------* |
View r7c9=45 with fin (9)
If r7c9=45 then (5=3)r6c4-(3=9)r9c4-r23c4=r3c5-(9=4)r3c9-(4=5)r7c9; r6c9<>5
If r7c9=9 then (9)r7c9-r7c2=r9c3-(9=3)r9c4-(3=5)r6c4; r6c9<>5
Also, a Kraken x-wing(5)r36c45 with Kraken fin (5)r6c9 results in r7c5<>5 which then leads to r7c9<>9
If Kraken fin is true: (5)r6c9-(5=3)r6c3-r6c5=(3-5)r7c5;
Ted |
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peterj
Joined: 26 Mar 2010 Posts: 974 Location: London, UK
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Posted: Fri Jun 03, 2011 2:49 pm Post subject: |
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I became obsessed with all those 49s! An oddagon/impossible-loop and a remote-pair entwined...
Code: | *--------------------------------------------------------------------*
| 49 2 49 | 7 1 3 | 8 5 6 |
| 5 8 7 | 49 2 6 | 149 *49+1 3 |
| 1 3 6 | 459 59 8 | 2 7 *49 |
|----------------------+----------------------+----------------------|
| 2 *49 35 | 6 8 579 | 34579 349 1 |
| 6 7 35 | 1 4 59 | 359 2 8 |
|*49 1 8 | 35 357 2 | 6 *49 7-5 |
|----------------------+----------------------+----------------------|
| 7 *49 2 | 8 359 1 | 3459 6 *49+5 |
| 3 6 1 | 2 579 457 | 4579 8 4579 |
| 8 5 49 | 39 6 47 | 13479 1349 2 |
*--------------------------------------------------------------------* | Oddagon creates a strong link (5)r7c9=(1)r2c8
Code: | *--------------------------------------------------------------------*
| 49 2 49 | 7 1 3 | 8 5 6 |
| 5 8 7 |*49 2 6 |*49+1 149 3 |
| 1 3 6 | 459 59 8 | 2 7 *49 |
|----------------------+----------------------+----------------------|
| 2 49 35 | 6 8 579 | 34579 349 1 |
| 6 7 35 | 1 4 59 | 359 2 8 |
| 49 1 8 |(35) 357 2 | 6 49 7-5 |
|----------------------+----------------------+----------------------|
| 7 *49 2 | 8 359 1 | 3459 6 *49+5 |
| 3 6 1 | 2 579 457 | 4579 8 4579 |
| 8 5 *49 |(39) 6 47 | 13479 1349 2 |
*--------------------------------------------------------------------* | Almost-remote-pair would eliminate (9)r9c4 making r6c4=5
The fins and guardians are clearly intertwined!
Consider the oddagon/impossible-loop...
Either (5)r7c9 ...
or if not then (1)r2c8 ... so r2c7<>1 & r7c9<>5 and the remote-pair exists, so r6c4=5
In either case, r6c9<>5!
As an "AIC"...
Code: | oddagon(49)[(5)r7c9=(1)r2c8] - (1)r2c7&(5)r7c9=remotepair(49) - (9=3)r9c4 - (3=5)r6c4 ; r6c9<>5 |
Having wasted 30 mins of my life on a pair of digits, I went back to find a humbling-ly simple two-stepper (which didn't include any remote pairs)!
Quote: | xyz-wing(35-9)r7c5 ; r8c5<>9
w-wing(49) r7c2, r3c9 ; r7c9<>4 |
Ted, it looks like what SE would call a "cell forcing chain"? Same elimination as a bove and some similar fragments. |
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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Fri Jun 03, 2011 6:06 pm Post subject: |
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It's interesting how peterj's second solution reduced the six steps from my solver to two necessary steps.
My solver also listed this single-stepper SIN: 5r6c9 5r3c4 4r3c9 9r7c9 9r8c5 => [r3c5]=EMPTY
Which led me to this simple Kraken Cell scenaro:
Code: | (4)r7c9 - (4=9)r3c9 - ( 9)r3c5
(5)r7c9 - r6c9 = r6c4 - r3c4 = (5-9)r3c5
(9)r7c9 - r8c79 = r8c5 - ( 9)r3c5
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Sun Jun 05, 2011 4:40 am Post subject: |
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XYZ-Wing (359); r8c5<>9
XY-Wing (495), flightless with transport; r6c9<>5 |
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