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 Hard patterns 
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Posted on: Tue Jul 24, 2012 12:08 pm




Posts: 246
Location: Lisbon, Portugal
Joined: Sun Sep 18, 2011 5:40 pm
Post Re: Hard patterns
Yes, Madlo, I agree with you. This is a very hard puzzle with so many combinations! There are many days ( 2 months (?), 3 months ? ) I gained the golden star every day. But today I gave up!
Any way, I applaud a new diagram. Many weeks ago the 9x9 patterned was always the same. But Patrick had another patterned diagram 9x9 that disappeared from the arena. Why?

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Posted on: Tue Jul 24, 2012 10:32 pm




Posts: 490
Location: Ladysmith, BC, Canada
Joined: Fri May 13, 2011 1:37 am
Post Re: Hard patterns
I too spent about an hour using some T and E but each one led nowhere and finally gave up......this has to be one of the hardest puzzles I've ever seen.....I hope this is not a new trend (as I wasn't able to do the 10x10 either nor the bitwise puzzle (don't understand this "stuff" anyways.....just "too old for new tricks")).......when I first joined this site over 2 years ago, I had trouble getting past the 6x6's but slowly learned how to do the 8x8's and up; but, recently I've been "running into brick walls" as the puzzles have been coming more intricate with the larger cages and increased level of difficulty.....me thinks it is time to spend less time on this site......and I don't think I'm the only one because when you look at the number of users that solve all the puzzles up to the medium 8x8, there are over 300 solvers/puzzle but then the 8x8 bitwise with about 60 solvers and then this #*+!* 9x9 with 30 solvers and the 10x10 with about 60 solvers.....tells you that these 3 puzzles are for the gifted people on the site and of course allows them to get separation from the rest of the masses in whatever ranking scheme you choose......fair??......from my point of view.....no.....from theirs probably yes!.....if this site was advertised as a job I'm sure one of the criteria would be "don't apply unless you have a Math/Spatial configurations of > 130"!!!


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Posted on: Tue Jul 24, 2012 10:46 pm




Posts: 163
Joined: Thu May 12, 2011 11:51 pm
Post Re: Hard patterns
I would be curious to hear from those who did solve today's 9x9 as to what their key maneuvers were.


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Posted on: Wed Jul 25, 2012 12:43 am




Posts: 422
Location: Canada
Joined: Fri May 13, 2011 2:43 am
Post Re: Hard patterns
sjs34 wrote:
I would be curious to hear from those who did solve today's 9x9 as to what their key maneuvers were.

I feel positive that you would get a more detailed and fine analysis from clm, but very very briefly from my end...

Not being used to the pattern, I stared at it for some time too. But then figured I would start from the right columns (I don't know which numbers of letters but more on the right side) where more numbers were already filled. After I found a few more numbers for those columns it allowed me to have enough information to figure out some other cells by taking the sum of the bottom rows. Anyway, that's how I started. After a point you're left with all + cages around the outside for the last step of logically figuring out which numbers go in those spots. Sorry this doesn't say very much. If you want it very specific, you'll probably have to wait for clm or someone else.

Nice to do a different pattern though. It was welcome.


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Posted on: Wed Jul 25, 2012 12:44 am




Posts: 690
Joined: Fri May 13, 2011 6:51 pm
Post Re: Hard patterns
sjs34 wrote:
I would be curious to hear from those who did solve today's 9x9 as to what their key maneuvers were.


I used the parity rule to start. For instance: g4 + g6 must be even (parity for the three rightmost columns) since "6x" is odd (with [1,3] or with [1,6]). Consequently [4,8] must be excluded for "12x" due to g4 = 8 >>> g6 = 9 because then g4 + g6 would be 17. Also [3,9] must be excluded because being g4 odd (3 or 9) g6 should be odd, that is, g6 = 9 and then g4 = 3, f4 = 9 and f6 = 8. Observe that in this case "5-" should be [1,6] (unique) with f8 = 1, with the consequence of the impossibility for the cage "6x" because neither [1,6] or [2,3] could be filled (this last due to g4 = 3 and g5 = 2).

So we have arrived to the only "12+" = [5,7] with f4 = 7 and g4 = 5 (well with the addtional d1 = 7). As a consequence, g6 = 9 (to make the even sum with g4 = 5) and f6 = 8. Also "7+" = [3,4] (unique). Observe that "13+" is unique with b3 = 5 and b4 = 8.

Consider now the parity for the three leftmost columns: c4 + c6 must be even and this means that d4 + d6 is also even, right?. Now you can determine (looking to the parity of the three central columns) that the cage "252x" is even ([1,6,6,7] or [2,3,6,7]) and consequently, since "8x" is obviously [1,8], you arrive (considering now the parity for the three upmost rows) to: b3 + h3 even and then h3 = 9 and h4 = 6.

Again with the parity conditions it's very easy to see that d6 = 6 and consequently, to make the even sum, d4 = 4 (c4 = 3) (c6 has the candidates 5 and 7) because [5,6] or [6,7] are the only allowed possibilities for "1-" (c6-d6) (it's very easy to see that [2,3], [3,4] or [4,5] are not possible and, logically, [1,2], [7,8] or [8,9] are forbidden). Etc. ... the full solution is extense.

Perhaps this helps.

Reedit. Another tips: The sum of the content of the cages "2-" (h6-h7) and "6x" is 13. Also more parity conditions: b7 + h7 is even (considering the parity for the three bottom rows) and, consequently, b6 + h6 is even. After the first steps mentioned I went (in a similar way as sneaklyfox) to determine that "2-" (h6-h7) is [3,5] (being impossible [2,4] when the possibilities for the three bottom rows are analyzed).

Reedited to add a clarification.


Last edited by clm on Wed Jul 25, 2012 7:41 am, edited 4 times in total.



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Posted on: Wed Jul 25, 2012 12:55 am




Posts: 13
Joined: Sun Mar 04, 2012 6:46 pm
Post Re: Hard patterns
beaker wrote:
...and I don't think I'm the only one because when you look at the number of users that solve all the puzzles up to the medium 8x8, there are over 300 solvers/puzzle but then the 8x8 bitwise with about 60 solvers and then this #*+!* 9x9 with 30 solvers and the 10x10 with about 60 solvers.....tells you that these 3 puzzles are for the gifted people on the site and of course allows them to get separation from the rest of the masses in whatever ranking scheme you choose......fair??......from my point of view.....no.....from theirs probably yes!.....if this site was advertised as a job I'm sure one of the criteria would be "don't apply unless you have a Math/Spatial configurations of > 130"!!!


Well, if it can put you at ease somewhat: There are some other reasons why the larger ones are solved less often. I've been netting some consistent gold stars lately, but not today (Tuesday). There reason is very prosaic: I've been on the road the whole day. Since I knew this up front, I made sure to solve some puzzles last night already before bed time (I'm living in the EU), but I didn't even try the first 8x8. Since I normally work my way upwards from the easy ones, it's only natural that sometimes my real life leaves me without enough time to even start the larger ones. I've seen other people write here that they also prefer to do the puzzle's in order, so I'm not alone...

For the rest: persistence is king. If you can solve the 8x8s other than "by just having luck", you can also get to the level of solving the 10x10. Similarly, bitwise OR is also not hard once you've had the right mental click about how the operator works. No one's too old to learn.


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Posted on: Wed Jul 25, 2012 1:51 am




Posts: 490
Location: Ladysmith, BC, Canada
Joined: Fri May 13, 2011 1:37 am
Post Re: Hard patterns
mce: you are how old?


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Posted on: Thu Jul 26, 2012 3:15 am




Posts: 13
Joined: Sun Mar 04, 2012 6:46 pm
Post Re: Hard patterns
beaker wrote:
mce: you are how old?


Much much older than you statistically might expect. Sadly. [sad] And yet still learning. [biggrin]


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