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Submitted by: Gath

 Indicate which comments you would like to be able to see GeneralJokesOtherSudoku Technique/QuestionRecipes
 1. Note triple 349 at g8/h78.Unique possibilities to 25.2. Whether g5=1;OR g6=1,e6=9=d1,g1=2,h1=5=g5;i4=6.UP81. 31/Dec/10 12:33 AM |  |
 SSTS -> UP 42;YWS : 1g6=(1-6)g5=614-(6=1)e4 : -1e6; SSTTE. 31/Dec/10 1:24 AM |  |
 SSTS -> UP 42;YWS : 1g6=(1-6)g5=6i4-(6=1)e4 : -1e6; SSTTE. 31/Dec/10 1:25 AM |  |
 very easy - 7:10 31/Dec/10 1:55 AM |  |
 Looks like a fire sunset. 31/Dec/10 1:56 AM |  |
 SE=7.1 31/Dec/10 2:12 AM |  |
 Hi, JC Van Hay, SSTS includes that YWS as part of its Techniques Set, so IMO, you should have said 'SSTS ->UP 81." 31/Dec/10 2:24 AM |  |
 I missed the locked 2s at ab8. So UP42 in step 1,as JC says. 31/Dec/10 2:43 AM |  |
 JC (and Niel): After e6=9=d1 (UP44),I think you still need another step. Unless I have missed something else. 31/Dec/10 3:02 AM |  |
 Hi Neil, Mmm ... Only the simplest XY-Wing is in the Sudopedia list of SSTS.Nevertheless, I would agree with you! As I often consider the following techniques as part of the SSTS :Locked Subsets, Template/Nishio , Forbidding Matrices of dimension 2 and 3, XY Chains of any length. Therefore, in particular : puzzle rated less than 7.2 => SSTS -> UP81 ! JC 31/Dec/10 3:46 AM |  |
 Hi Alfred, After YWS, Pointing 5 in Row 3. BTW, here is your AIC : 1g5=g6-(1=9)e6-d6=d1-5d1=gh1-g2=6g2 : -6g5;STTE. Note : The AIC and the YWS may be viewed as triggered by the same cell g5 containing twins. JC 31/Dec/10 3:49 AM |  |
 It's a beautiful photo. I'll bet there was a pretty good storm coming in! 31/Dec/10 4:31 AM |  |
 1. SST to UP=42.2. (1=6)e4-i4=(6-1)g5=g6 => e6<>1UP=81. 31/Dec/10 5:06 AM |  |
 Thanks JC.Bit blind tonight. And thanks for the AIC translation. Regards, Alfred. 31/Dec/10 5:42 AM |  |
 It is a very pretty sunset! Were these storm clouds? 31/Dec/10 6:07 AM |  |
 Debby, the intersting thing is that I am looking east with the sun setting behind me. They were storm clouds but I do not think we got any rain. 31/Dec/10 9:30 AM |  |
 An epic Epping sunset. 31/Dec/10 9:34 AM |  |
 Easy today - 13:01. 31/Dec/10 9:53 AM |  |
 note: just posted eureka path for unsolved tough Aug-21-07 SE=8.3. 8 steps w/o kraken. A lot of flex in path direction, other eureka players are invited to find a more efficient path. 31/Dec/10 10:06 AM |  |
 note: I'm sure UP-chainers will spot the early back door in the above and gloat over their find - (some might even trot out a dressed up 20+ depth FC+SST chain 'proving' the back door - eureka players will calmly ignore this errant display). 31/Dec/10 10:17 AM |  |
 (you play or used to play chess Alfred - their are rules and constraints in how one plays the game - touch piece, move piece etc. - according to Neil this is illogical hmmm?) 31/Dec/10 10:30 AM |  |
 farpointer: Rules are rules of course, which for chess,are regulated by the FIDE. For sudoku, there is no international body that says AICs are the only way you are allowed to solve puzzles. Some chess players constrain themselves to playing always the same opening.That is their choice. They don't expect others to do the same. 31/Dec/10 11:31 AM |  |
 -not the point, Neil's assertion was that constraints are illogical, patently absurd. 31/Dec/10 1:01 PM |  |
 BTW: it's an interesting back door in the above puzzle, on a digit of an aur - false (the incorrect guess, leads to one UP, true goes from 30 to 81. 31/Dec/10 1:06 PM |  |
 sotir: are Aug-19-07 and Aug-18-07 ratings interchanged? the SE=8.3 solves like the SE=7.2 and visa versa (in which case there is still an unsolved SE=8.3). 31/Dec/10 5:10 PM |  |
 Hi farpointer and others, Maybe I didn't explain my self correctly with my assertion. Boolean Algebra/Logic is based on a set of mathematical rules which are intended to help people solve problems of various kinds. Sudoku is a number puzzle with very simple rules, which can More... 31/Dec/10 10:08 PM |  |
 Hi farpointer, sotir and others, Quite often people on this site show their findings, and sometimes say something like 'this may not be the most efficient path, others may do better'. If solving using Eureka/AICs/etc is as logical as some people state, there can only be one true path - as logic would preclude the others. 31/Dec/10 10:12 PM |  |
 farpointer: rechecked:Aug 18/07 SE=7.2,Aug 19/07 SE=8.3 01/Jan/11 1:03 AM |  |
 Neil, Each aic is a theorem regarding the puzzle. But there is no a priori reason to believe that there is one and only set of aics that solve a puzzle in the most efficient manner. 01/Jan/11 8:49 AM |  |
 I would point out that thermodynamics contains a similar situation. We know that a macroscopic system can be described by a very large number of state functions (on the order of Avogadro's number), but the harsh reality is that only a handful of these are needed to characterize the parts of the system of interest. 01/Jan/11 8:55 AM |  |

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