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rh121711

 
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Sat Dec 17, 2011 1:11 pm    Post subject: rh121711 Reply with quote

Form vs Boolean
Code:
 *-----------*
 |..6|..1|3..|
 |27.|8..|..1|
 |..1|.62|...|
 |---+---+---|
 |.3.|...|..7|
 |.1.|.4.|.8.|
 |6..|...|.3.|
 |---+---+---|
 |...|12.|8..|
 |9..|..3|.24|
 |..7|4..|6..|
 *-----------*
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Sat Dec 17, 2011 3:24 pm    Post subject: Reply with quote

After basics:
Code:
 *-----------------------------------------------------------*
 | 8     459   6     | 579   579   1     | 3     459   2     |
 | 2     7     59    | 8     3     4     | 59    6     1     |
 | 3     459   1     | 59    6     2     | 7     459   8     |
 |-------------------+-------------------+-------------------|
 | 5     3     249   | 269   89    689   | 249   1     7     |
 | 7     1     29    | 3     4     59    | 259   8     6     |
 | 6     89    2489  | 259   1     7     | 2459  3     59    |
 |-------------------+-------------------+-------------------|
 | 4     56    3     | 1     2     569   | 8     7     59    |
 | 9     568   58    | 567   57    3     | 1     2     4     |
 | 1     2     7     | 4     589   589   | 6     59    3     |
 *-----------------------------------------------------------*


The "5s" were productive for me.

The major damage is done by either a AUR(89)r49c56[(5)r9c56=(6)r4c6]-r7c6=(*6-7)r8c4=(7)r8c5; r8c45<>5
or an equivalent (5)r8c3=(5)r2c3-r2c7=r56c7-r6c9=r7c9; r7c2<>5

Coloring on (5) completes the puzzle.

Ted
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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium

PostPosted: Sat Dec 17, 2011 3:42 pm    Post subject: Reply with quote

Code:
+---------------+-------------------+-------------------+
| 8  49-5  6    | 579    579  1     | 3       459  2    |
| 2  7     9(5) | 8      3    4     | 9(5)    6    1    |
| 3  49-5  1    | 59     6    2     | 7       459  8    |
+---------------+-------------------+-------------------+
| 5  3     249  | 269    89   689   | 249     1    7    |
| 7  1     29   | 3      4    9(5)  | 29(5)   8    6    |
| 6  89    2489 | 29(5)  1    7     | 249(5)  3    9(5) |
+---------------+-------------------+-------------------+
| 4  6(5)  3    | 1      2    69(5) | 8       7    9(5) |
| 9  568   8-5  | 567    57   3     | 1       2    4    |
| 1  2     7    | 4      589  589   | 6       59   3    |
+---------------+-------------------+-------------------+

"Rank 2 or Remotely Finned Sashimi" Jellyfish(5R2567) :

t-Chain on 5s :r2c3=r2c7-r5c7=r5c6-r6c47(#1)=r6c9-r7c(6#2)9=r7c2

Or

TM on 5s

r2c3 r2c7
     r5c7 r5c6
     r6c7 r6c4 r6c9
r7c2      r7c6 r7c9

=> 5r2c3=5r7c2 => -5r13c2, -5r8c3

Note : The Remote Fin is 5r6c4. If r6c4=5, then 5r2c3=5 as the TM directly shows it.
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arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Sat Dec 17, 2011 5:52 pm    Post subject: Reply with quote

A lot goes on with 5's Very Happy

Tried to code this with eureka. Had to give up. help Confused
Code:
 *-----------------------------------------------------------*
 | 8    *459   6     | 579   579   1     | 3     459   2     |
 | 2     7    f59    | 8     3     4     | 9-5   6     1     |
 | 3    *459   1     | 59    6     2     | 7     459   8     |
 |-------------------+-------------------+-------------------|
 | 5     3     249   | 269   89    689   | 249   1     7     |
 | 7     1     29    | 3     4    *59    |e259   8     6     |
 | 6     89    2489  | 259   1     7     |*2459  3    *59    |
 |-------------------+-------------------+-------------------|
 | 4    *56    3     | 1     2    *569   | 8     7    *59    |
 | 9     568   58    | 567   57    3     | 1     2     4     |
 | 1     2     7     | 4     589   589   | 6     59    3     |
 *-----------------------------------------------------------*
Finned Franken Jellyfish
(5)fin:r2c3 = (5)endofin_franken_jellyfish:r57b16\c2679 plus endofin: r5c7 ==> r2c7<>5

added eureka code--Thanks ronk!
added endofin code


Last edited by arkietech on Sun Dec 18, 2011 2:06 am; edited 2 times in total
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ronk



Joined: 07 May 2006
Posts: 398

PostPosted: Sat Dec 17, 2011 6:14 pm    Post subject: Reply with quote

arkietech wrote:
Tried to code this with eureka. Had to give up. help Confused
...
Finned Franken Jellyfish

How about ... (5)fin:r2c3 = (5)franken_jellyfish:r57b16\c2679 ==> r2c7<>5

In cover set terms, the finned franken jellyfish has (defining) base sets r57b16 and cover sets c2679 + r2. Nice find!

[edit: add the following]
I didn't notice that r5c7 is in the intersection of both r5 and b6 base sets, i.e, an "endo-fin", a fin cell regardless of the chosen cover sets.

Either r2c3 or r6c7 may be chosen as the "local-fin" and choosing r6c7 allows one to combine r5c7 and r6c7 in one fin-sector c7. Therefore, I revise the above to:

(5)fin:r56c7 = (5)mutant_jellyfish:r57b16\r2c269 ==> r2c7<>5


Last edited by ronk on Tue Dec 20, 2011 2:51 pm; edited 1 time in total
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SudoQ



Joined: 02 Aug 2011
Posts: 127

PostPosted: Sat Dec 17, 2011 6:37 pm    Post subject: Reply with quote

You can also show that r6c2<>9:
Code:
r6c2=9 -> r6c9=5 -> r6c4<>5 -> r5c6=5
                 -> r7c9<>5 -> 
      -> r8c2<>6 -> r7c2<>5 -> r7c6=5
/SudoQ
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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium

PostPosted: Sat Dec 17, 2011 7:36 pm    Post subject: Reply with quote

ronk wrote:
arkietech wrote:
Tried to code this with eureka. Had to give up. help Confused
...
Finned Franken Jellyfish

How about ... (5)fin:r2c3 = (5)franken_jellyfish:r57b16\c2679 ==> r2c7<>5

In cover set terms, the finned franken jellyfish has (defining) base sets r57b16 and cover sets c2679 + r2. Nice find!

Hmmm .... I am still confused by Fish Theory ...

I don't understand why (5)franken_jellyfish:r57b16\c2679 => r2c7<>5 ! (and -5r78c2, but : not -5r9c6 and the cannibalism -5r6c9 ????? w/o any further analysis)

On the other hand, an Eureka equivalent of Dan's jellyfish is :

    Kraken Row 5R7 => -5r2c7

      r7c2-r13c2=r2c3
      ||
      r7c6-r5c6=r5c7
      ||
      r7c9-r6c9=r56c7

    => Derived SIS [r2c3(local fin),r5c7(endo-fin),r6c7] => -5r2c7
JC
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

PostPosted: Sat Dec 17, 2011 11:23 pm    Post subject: Reply with quote

W-Wing (59) in r2c7 and r7c9, SL 9 in c8; flightless with transport to r13c2; r7c2<>5
Coloring with pincers in r1c8 and r9c5; r9c8<>5
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ronk



Joined: 07 May 2006
Posts: 398

PostPosted: Sun Dec 18, 2011 12:26 am    Post subject: Reply with quote

JC Van Hay wrote:
ronk wrote:
How about ... (5)fin:r2c3 = (5)franken_jellyfish:r57b16\c2679 ==> r2c7<>5

In cover set terms, the finned franken jellyfish has (defining) base sets r57b16 and cover sets c2679 + r2. Nice find!

On the other hand, an Eureka equivalent of Dan's jellyfish is :

    Kraken Row 5R7 => -5r2c7

      r7c2-r13c2=r2c3
      ||
      r7c6-r5c6=r5c7
      ||
      r7c9-r6c9=r56c7

    => Derived SIS [r2c3(local fin),r5c7(endo-fin),r6c7] => -5r2c7

I missed the fact that 5r5c7 is an endo-fin, which complicates the fish POV. Moreover, it's actually an sashimi franken jellyfish, which further complicates the unfinned analysis. Therefore, I agree your kraken row POV is better.
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Sun Dec 18, 2011 3:42 am    Post subject: Reply with quote

I don't distinguish an endofin cell from a non-endofin cell because it's irrelevant. If a cell is in more base sectors than cover sectors, then it's a fin cell. All that matters is if the fin cells directly or indirectly see the elimination cells.

In this case, I get:

Code:
finned/Sashimi Franken Jellyfish r57b16\c2679 w/fin cells:r2c3,r5c7 => r2c7<>5

Where the fin cells directly see the elimination cell.


As for JC's confusion, I can only address part of it. If the fin cells didn't exist, then r8c2<>5 and r9c6<>5 would also be true. However, these cells aren't directly seen by the fin cells, and no effort was made to show that they might indirectly be seen by the fin cells.


As for transforming the fish notation into Eureka notation, I don't see why.

Regards, Danny
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ronk



Joined: 07 May 2006
Posts: 398

PostPosted: Tue Dec 20, 2011 5:52 am    Post subject: Reply with quote

daj95376 wrote:
If a cell is in more base sectors than cover sectors, then it's a fin cell.

For a useful fish, if a cell (with a candidate) is a member of two base sectors, have you ever seen it not be a fin cell? If so, I would love to see an example.
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Tue Dec 20, 2011 5:09 pm    Post subject: Reply with quote

ronk wrote:
For a useful fish, if a cell (with a candidate) is a member of two base sectors, have you ever seen it not be a fin cell?

Assuming that we're talking about a vanilla 9x9 Sudoku and NxN Fish where no base/cover sector is used more than once, then any cell in two base sectors can only be in one cover sector (at most). So, I've never seen such a cell be anything other than a fin cell.

Now, when one uses Nx(N+k) Fish as Obiwan proposed, then it's possible to have a cell in two base sectors and two cover sectors -- with one cover sector repeated. Of course, the concept of additional cover sectors -- fin sectors -- negates the possibility of a fin cell.

Unfortunately, I can't recall a (specific) fish where a cell is in three cover sectors. I'm not sure how Obiwan's fin sectors would work in this case.

Regards, Danny
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ronk



Joined: 07 May 2006
Posts: 398

PostPosted: Wed Dec 21, 2011 1:02 pm    Post subject: Reply with quote

daj95376 wrote:
ronk wrote:
For a useful fish, if a cell (with a candidate) is a member of two base sectors, have you ever seen it not be a fin cell?

Now, when one uses Nx(N+k) Fish as Obiwan proposed, then it's possible to have a cell in two base sectors and two cover sectors -- with one cover sector repeated. Of course, the concept of additional cover sectors -- fin sectors -- negates the possibility of a fin cell.

Then it's a fin cell with adequate cover, but it's still a fin cell.
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