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Submitted by: uno hu

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Today's puzzle is an ER 9.0. Should be a tough one. I may have a quick solution that involves one complex step. I will probably blog the step.

Provided I have not erred in my haste, the step is a continuous network using the following "at least one is true" sets:
(4)rows 3 More...
05/Aug/10 12:22 AM
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Lovely place.
05/Aug/10 12:39 AM
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Another nice photo Wendy!
05/Aug/10 12:52 AM
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quite tough for me: UP=26
1.Kraken Cell(169)e9=> g8<>4, UP=28
2.loop (9=6)a9-(6=4)a8-c8=c2-e2=e6-HP(39)e46=(9)e9
=> c9<>9,a7e6<>6,a27f2i8<>4,e6<>8; UP=37
3.(1=269)aeh9-(2=6)i8-i1=e1 => e1<>1; UP=81.
05/Aug/10 1:02 AM
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1) Start 23 UP 26
2) IMO, the continuous network is an efficient approach to this one:
[(4=6)a8 - (6=9)a9 - (9)e9 = HP(93)e46 - HP(34)e46 = (4)e2 - (4*)f3 = (4*)a3 loop] = (4*)b3 -
[(4=3)b4 - (3)c45 = (3)c1 - (3)g1 = HP(39)g56 - HP(94)g56 = (4)g8 - (4*)i7 = (4*)b7 loop] = (4*)a7 LOOP
05/Aug/10 1:02 AM
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probable loop of step 2 is a poor cousin of Steve's massive continuous network - is there an "easy" algorithm for finding these and if so is the method cloaked in a masonic veil of secrecy?
05/Aug/10 1:15 AM
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for me - chaining over 5 sets is too deep; plus not one but two AAIC's in one chain - geeze (sans the SECRET METHOD).
05/Aug/10 1:20 AM
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farpointer: I am not sure about the algorithm perspective. I have some clue about pattern matching perspectives, but that often is a self-fullfilling prophecy - one finds what one seeks, etc.

I would hardly call your step 2 a "poor" cousin. In fact, it is, imo, a clue that the More...
05/Aug/10 1:26 AM
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Farpointer wrote: "for me - chaining over 5 sets is too deep; plus not one but two AAIC's in one chain"

"sets" seems to be a rather subjective term. One can see the entire mega-chain of 12 native SIS as simply two sets. That, imo, is no different than using ALS, etc. It just happens that these sets are in differently orthodox containers.
05/Aug/10 1:29 AM
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Complexity is always a bit subjective. So, although you obviously think the continuous network is more complex, the following objective data exists:
Your kraken step uses more "native sets". It also uses more "derived sets" if one counts the deriviations More...
05/Aug/10 1:39 AM
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Steve: there are usually 200..300 native sets to deal with. The combinations 12 in 300 is astronomic - ie. you have some method you are unwilling to impart (saying that it is a 'pattern' is a gloss which evades the question).
05/Aug/10 1:40 AM
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BTW - my solution uses no 'derived' weak inferences, the chains from each possible of the kraken cell use only native strong sets, the two chains which complete the solution use only native strong and weak links. Max chain depth is 5, in the loop - something achievable by a mere mortal before he despairs.
05/Aug/10 1:56 AM
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I hardly wish this to become acrimonious. However, please be consistent. You can choose some arbitrary measure and say something about complexity, if you wish. But, if we are making comparisons, some consistency in your implied measures is required. By your accounting then, for More...
05/Aug/10 2:13 AM
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Steve wrote my "step 2 ... is, imo, a clue that a massive loop must exist." Step 2 is not possible until step 1 is complete and so can not be a clue, because it doesn't yet exist.
05/Aug/10 2:25 AM
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Farpointer wrote:
Step 2 is not possible until step 1 is complete and so can not be a clue, because it doesn't yet exist.

I have never yet, nor shall I ever, create a step. They all exist, already. We just find them. To argue that it "does not yet exist" is, well, More...
05/Aug/10 2:32 AM
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Steve - I don't recall claiming the kraken's depth was 1, the static chains stemming from each possible have a look-ahead depth max of 4 sets. I never made a judgement good/bad on your solution; in fact it is a scintillating curiosity! (fain?)
As to 'derived' strong sets vs. 'native'; I have no More...
05/Aug/10 2:41 AM
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Steve: saying that all is current in the present implies knowledge of the end - mortals are not granted this omniscience and must proceed stochastically step by step OR reverse engineer the solution.
05/Aug/10 2:48 AM
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Not solve this tough, just read Steve’s and farpointer’s comment
As I understand about “length” or “dept” on Steve’s count is meant that: ALL STRONG SET on that move, right? => All Kraken must be at least “length” 4.
Example: kraken cell (ABC) => ... More...
05/Aug/10 2:50 AM
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Hi Gath, Are you able to provide asbestos web pages to prevent my PC burning up? Best regards, Neil
05/Aug/10 3:02 AM
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Neil: surely the acrimony is one-sided. I made two light-hearted comments and incurred a firestorm from Steve (why? I have my stochastic guess) - naturally I defended.
05/Aug/10 3:24 AM
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farpointer wrote: “...and incurred a firestorm from Steve (why?...)...”
Hmm..., I think that you should be read careful Steve’s comments first before saying that
Everyone always think that – even me in sometimes : “I’m the best”. But IMO, the best is only ONE, so if you like to become “the best”: at first you must be follow “the best”
05/Aug/10 3:56 AM
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, Wendy!
05/Aug/10 4:05 AM
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Play nice children
05/Aug/10 4:19 AM
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First, I apologize for the apparent tone in my replies to Farpointer. I truly do not mean any offense.

Secondly, I would like to be granted the right to explain myself. I have, over the years (yes, it has been years - yikes!) had discussions about some of the same stuff more than once. More...
05/Aug/10 4:53 AM
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The concept of counting is the simplest of concepts to find an SPM. In the case of a group of SIS that are entirely Bivalues or BiLocals, the count is rather trivial.

The rules of the count. Add at any time and in any arbitrary fashion any SIS one wishes to the mix. The total count More...
05/Aug/10 5:19 AM
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A three SIS bivalue chain would have a "look ahead" of one if one starts in the middle. That was the intent of my abstract demonstration. You did confirm that by your answer. You seemed to deny it, but what you wrote is consistent with agreement, unless I am missing More...
05/Aug/10 5:31 AM
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It may take some considerable time for me to properly attach the puzzles you mentioned. I have a completely different mode of deduction in mind for those puzzles. Unfortunately, I have not completely developed the theory yet. I can say that it looks promising to use More...
05/Aug/10 5:35 AM
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Steve: one must also know that the 12 of 300 or so sets is a locus of investigation for your matrix - in your example 2..3 intertwined krakens -- at least an order of magnitude larger search space than the 3 points of one kraken (but those magic twelve, all conveniently linkable just popped out as More...
05/Aug/10 6:47 AM
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ttt: calm yourself! I tilt not at Sudoku Gods and make no pretense at being one. My considerable talent as a computer programmer is another matter entirely!
05/Aug/10 6:56 AM
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Please review what you are writing more carefully. I never claimed that you said your kraken was not complex. I have merely asserted, repeatedly, that measures of complexity are subjective. If you truly find another meaning, then either I have misspoken, or you have misread.
05/Aug/10 7:14 AM
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Steve: I have been "around the block" many times in the half century (yikes) the earth has circled it's sun. You err if you assume I am naive. BTW - computers are astonishingly good at pattern matching and parallel processing as they also are at processing with incomplete and noisy data - More...
05/Aug/10 8:04 AM
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Hey Men, this is a very interesting discussion and one that my computer programmer mate will take on, if I can locate him somewhere in the ether!! Maybe Gaia also would have some bearing on it!
05/Aug/10 9:10 AM
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about 1 hour
05/Aug/10 11:32 AM
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Hi Jyrki,
Thanks for your note yesterday - I have replied on that page. Best regards, Neil
05/Aug/10 3:15 PM
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Neil, you're welcome!

This was quite tough, so I'm glad to see nobody found simple chains resolving it.

At 26 filled I derived a contradiction, if 4 is in gi8 (after a few steps you will have created a pair 18 in de8 and locked 6 into e12 forcing e9=1, which is a no-no). That took More...
05/Aug/10 5:03 PM
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Thanks for your post above, but it is time for me to do other things (Sudoku from about 6AM until about 9 or 10AM UK time). I will look at your solution either very late today, or tomorrow morning.
Best regards, Neil
05/Aug/10 6:09 PM
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Preface: The interchange between Farponter and I began on August 1, 2010. Farpointer asserted that kraken complexity might be evaluated in a particular fashion. I noted there that such imo such complexity measures are entirely subjective. Most of our interchange above (before we digressed) was More...
06/Aug/10 12:12 AM
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Steve: your solution is of course brilliant and better than I could achieve at this point in time (I never denied this) - I haven't yet attempted to implement 'kraken groups' on anything but cells and units, but may do so in a limited way in the future. Also it is quite difficult for me to perceive when an XWing might be usefull as a bool node - two reasons I couldn't reach your mighty loop.
06/Aug/10 1:51 AM
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10/Sep/10 11:12 PM
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