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# 2012-11-17: Puzzle - First to solve wins

For years I've had an idea in my head about a way to hide some information in a bunch of numbers. I actually got around to coding an implementation and figured I'd run a competition. The first person who figures out what the famous landmark is described by the second set of numbers below and posts the correct answer in the comments wins $100.

## The hint

Here's a hint. The following numbers are a reference to the Eiffel tower:

5651256228

6704779064

3038223708

5949959984

0366479924

9867779808

3948559064

4070829058

5834526088

5320666502

6882068022

7469299991

9151111159

5882128204

9320093979

5289268474

9350097796

5581683024

7330968804

5648215222

3847223428

2166128637

7663999663

5336232325

9758955998

2840222244

5147115746

5796299729

9866282082

3583038580

7699199111

3663108038

9596057624

5462244788

3596210738

7426202503

8433665999

1438675594

8144545414

0937014971

7144114974

7144941929

3554365403

1181115811

7437973694

8338313788

9984490646

9728272998

0020330042

0736490682

0875010949

5489110698

8632422882

2048490788

5243235555

7109819849

7469569567

3242772234

5149789084

9163071510

5449749729

7165278451

3144703308

3219306782

8501804511

2043481782

9520070521

5827571585

2226626622

2721772761

6666680016

2226006281

2450038914

4033850484

6463747392

1800250994

7444937494

7655957962

0338340383

3938338394

0326338204

7831718394

6816343254

6479778768

6811743461

6835736685

6471564815

7417878788

0379330993

6291161116

1421627605

9692727105

6412425069

9321657205

6745716745

2091051209

1131342123

2003225067

5500057005

6199322434

6620729352

5870409656

6203051387

9709759337

2800402284

5527121375

5665565630

2525265452

0861810860

6911661699

1170507715

2828552888

1161500566

1861526025

1971674470

1578573975

1821421815

0710101570

9575070569

2323323231

2122713227

0265613577

6772001229

8247910237

9947276237

9502013271

## The puzzle

Given the above hint, what famous landmark do the numbers below refer to?

7225325327

9672997722

7447774673

8177777018

4178077328

7158326032

8950176323

0011977622

7042394616

3334334683

2957779620

4280440827

9949552904

1821034922

1419372683

9691250370

4320735684

1554950900

4266676462

7074171264

5585665458

5509990582

1301890762

3538960764

0916875258

2206671462

4993771463

1844480441

2949994257

5337374335

3064317306

2695493417

4385314257

3908473805

4427613407

1525193459

0169776079

3048343803

2260808226

6587178755

2540163274

3641318885

2588894260

6247839065

2568178904

8236118331

1793771333

6790229729

7962597527

1793786352

8932051575

7786566709

8290000650

8700290542

7168566062

5477219042

5010646981

3972219944

6602999062

6675666781

4994419947

4000113044

4666449362

5778837585

2248582352

5801054108

1373773313

2683632611

9476374118

1065433508

5900493418

6596232311

0611670763

9735142102

7285100083

9213925488

6281912898

7385687737

5731173130

9635666669

7213532231

2387416392

5739565930

2787425879

2487503746

2331532325

2297325222

1786476677

5479974549

5387858388

6700112054

3726112936

7937742083

5267013145

8989118928

1548545145

1311311133

3881613186

2052542051

8855081321

6561333881

5822959889

5993453484

5885753887

4495883459

3453559320

9918169881

9338334984

2121028925

5126095925

8983030378

7239967917

8161915166

7253457755

9826668929

2931013220

5439999433

3144884848

2485055280

3262424202

7769191177

3262146253

7964472988

3485071865

2264161801

3227429449

Post the answer as a comment below. ~~The first person to answer correctly with an acceptable explanation to how the answer was reached (rather than just a guess) wins $100, so make sure to use your correct e-mail address so I can contact you.~~

**Note #1:** People have noted that the numbers change whenever the page is reloaded. That's as expected. This puzzle is *not* an *encryption* as much as it is an *obfuscation*. That the numbers change is not important, as only the pattern in them will lead to the answer, which is of course constant.

**Note #2:** There was a bug in my post for a short while, which made the hint and puzzle basically the resolve to the same answer. This is fixed now. If you saved a copy the numbers before, just grab a fresh set.

## Solved!

The second landmark was discovered by Batuhan Bozkurt, congratulations! The challenge has not yet been met entirely, though so I've decided to set a new challenge with the same method. ~~The same $100 prize applies~~.

Redditor Bearasaurus has solved the final challenge too! For hints, check the followup post.

## Comments

Big Ben

I'm afraid Big Ben is not it. But be sure to include some explanation as to how the answer was reached, so I know it isn't just a random guess.

I "solved" your puzzle, but I assume not in the way you wanted.

After giving it quite some hours, I failed to find any specific pattern (with a reasonable kolmogorov complexity) that would lead me to an answer. But in Reddit, you mentioned that you would be interested in statistical approaches that would lead to an answer (which I assume you are interested for increasing the security of the obfuscation?) so I exploited the fact that your website gives fresh batch of numbers at each reload so I grabbed about 1000 sets (with intervals in between, hopefully not causing trouble to your website, it handled the requests like a champ) and got to cracking.

Now your HTML formatting implies 10x10 blocks of data for each set. So that was a starting point when I first began looking at the problem. The grid is 70 x 20 so that implies 14 secret codes, 7 for each row.

I looked for what was common for each 10x10 block in each of the samples I gathered from your site. I found out that for each 10x10 block some digits occasionally never appears; for example in block 0x 0y, not all digits have to appear but one always appears at least once.

Once I looked at the remaining digits (that are common in all blocks at a particular coordinate), for the "hint", I was faced by these digits:

0485130

0021739

These are the coordinates in the form of degrees-minutes-seconds (dddmmss as you gave away generously in Reddit) of Eiffel Tower.

Once I ran the same process for the puzzle, the result was:

0295845

0310804

Which is the coordinates for the Great Pyramid of Giza.

Maybe this is disappointing, I don't know. If the website hadn't provided fresh batch of numbers, this method would not work. I assume, to strengthen the obfuscation, you could make sure one digit always appears at least once; but as long as the distribution isn't random, I suppose the answer could be extracted.

I've tried many approaches before this; I'm pretty confident that the pattern is not based on neighborhood relationships (as the answer can appear on edges, though wrapping around could be employed but still with it I failed to detect any patterns). I think it doesn't have anything (or much) to do with arithmetic on the digits (like summing / subtracting them). I tried various row/column patterns and couldn't come up with anything.

I also analyzed the 10x10 blocks containing the answer digits only once (so if the answer is 0 for that block, 0 appears only once in that block). But saw no obvious pattern at all. So this beats me in that regard.

If I am eligible for the prize for my answer, I would kindly ask you to donate it to the Doctors Without Borders foundation. If you are uncomfortable about it for some reason, you can choose to donate it somewhere else you see fit.

Thanks for the challenge, and although my curiosity has been partly satisfied, I'm still waiting for the answer that will allow me to solve this using a pen and paper using a single set of numbers.

Batuhan, the answer is indeed correct. The Great Pyramid of Giza is the one I was looking for. The method you used is indeed not the one I was hoping for, as you haven't actually figured out the way the coordinates are encoded into the sets of numbers.

Still, I'm not one to dictate how the problem should be solved. I will make a donation to Doctors Without Borders for $100 in your name and post proof that I have done so.

Since I would very much like for somebody to solve the method, I'm including this static problem for a second attempt, and another $100. Being in a comment, the following set obviously does not change and encodes a third landmark.

2626513077384364666346599932245309032974209496921885110948315551555613

6549028370497764766953274173448611231555969009312435020244378244262894

9308377132331493394457637801172312372974892873367485438142538547446457

5987478672136633636156339295109196283474021313920015080695500005010510

9318473400638833698356337893287640679475088481921818727043921551931599

5758758671181690400516397336912974972974211231362065019596695870416497

1701226107698865022553554534544375771374969996927993180831110067651597

3203310324331357320447629709425333533533932743923435767555759732852649

0008077080336367751344339394399228589625005440340517458583553308156594

7467243472134765226056779555595344734475199118911888022882025906466417

0332300493776667648725560571112261196221231229957486429403779342535143

1366338577707417047142278890548676887286598087756091175002210326130060

5863902088494574497542911473583959753975898054668946115111760583633056

3673921092972792959782223331128568968982838265801286279605628360969080

5301986352763553665223261861393193111359891776463941295493449120391390

0463999640662807648743557375531417213379281451584481179187119326988940

4352555243298062697573961379660934698929891289118894828988929160129317

1871110111741174649945428445570098658283038728302510575750510526949009

3326333663020967498782260828822839081251556075505536114445618120357157

5602990599311067698721073220721651596922796029092045295295550390501233

The challenge now is to find the answer and a step by step description of how to extract the correct digits from it.

## Post a comment