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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:

5928899255

8631488846

1908909099

0138731703

1408742098

8938461087

1634882892

0438951763

0934150493

9528287797

9818763180

4535674740

4620708991

4633777634

1514141421

7668977998

9822669222

9200220002

3365385448

0863657592

5160504491

0130521475

5030553305

3600560396

2861326888

0355330330

8163636383

0910119097

0888888608

1477636847

5591951749

3165057447

5588081437

5413857049

3423719748

8308079848

6092120962

4845545455

6123737171

5066996656

4863580636

8090785667

5129738981

5045723993

5322978254

4093110404

6315151131

8061910069

4265555756

0067502622

4361992683

8567519607

8387398362

4095150353

6172002606

0880440008

9848898848

9019790099

1810729475

9870087249

9888729725

1640080957

9010599733

3265993461

8862997497

7375656540

3862566194

3063116001

3857585572

0383703730

8835989983

7282688227

1897721971

3114091943

9200210570

8508836571

1901331901

1176486174

9920991042

9028020509

3378718373

9881618611

2261222222

9525352505

3096119610

2621122143

3535132425

3891282807

2581285267

2645398414

7097500959

3854633154

4698778879

5468156454

3494583715

3850182123

4858763867

7604621789

6894138408

4662866428

7735075507

1181013180

1121111621

3519233400

3091311681

4100961180

5374210500

2537635641

0837725618

3209827618

4117838631

6425017719

1011991605

2213134112

1117717788

0031118031

2390225609

0852305050

6028128108

6693563955

8791379717

0851989398

0682548005

6022518200

6024119907

6051350051

## The puzzle

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

5737320273

4304010189

1227755289

6918810083

5582510275

5806656083

9539355379

8662826283

1444330419

4379027046

6131049521

7413443825

6517098329

3227997321

8418548415

2929929526

4899113849

9000210025

2625656352

4067470747

3489443998

2917777227

2469783821

4669677571

4625728769

3581486979

2989429706

4775545247

3493093034

7869876928

6772773368

3812079397

9688345248

8554803367

6695443939

7926173298

6764677320

1569672319

6759060218

9764785417

6259799655

9755675957

5864884865

9214841819

1527661519

8484684355

7419976807

3695984254

8971076287

5447775405

4288784357

7207070214

3733773487

2622876289

8581518015

9216661194

1211211247

0505750079

2195212279

6541145040

7881561270

6187412214

9586858247

8839317306

6753444210

6824444552

9628304571

8689339968

9724544929

5053450504

2824112278

6078585606

8733133388

4848384844

2984332241

8589355838

8082988552

4589359710

8683344463

2583109932

4032380138

9178146140

3182028944

9675031264

9000185971

9190779977

1684448261

7372132122

3049430444

9605050906

0630040268

8007887908

8220285220

3349333649

7347014668

6540917921

1746240261

5543984208

1909137760

4437684191

7607188131

0011584291

6958814338

7707777380

1613116031

2823128431

4481384238

9001084190

2368466622

5530805545

7863232667

5923772357

7469725643

2960885676

7563867200

2569904805

5823844347

5555585507

2720808237

3008370131

3775553176

5867813107

9470650237

7584407297

3819053571

9938388137

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