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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:

3267672761

6268142902

2297687750

6247983028

9167997669

5629625999

3492553395

2098090022

6249662434

3478204171

3597384241

0425851771

0122981890

0525353052

0297820208

5144955445

3443241433

5372883778

5130939150

5957222529

9979599599

9300993095

5907522709

5160561168

5100523309

9300591717

9956486216

3415816527

4467137125

9416053095

3405904215

8407998702

4626164212

3417417734

2549055455

8765856658

0083774087

2444442844

3203434230

3252532532

6854472270

3791131832

1553634972

8590677237

6368834080

3504605159

7540514327

7800684111

7895768821

3815711633

8890608906

7642266742

7504045557

7900447707

9933451214

6395413011

2125913025

2034850091

5145151054

7555151795

1170110217

9086853098

8818881821

8809434605

4394134887

6549214270

0253618260

7764334667

8887690786

0545858970

4405054810

1541114215

1830080138

2983293889

9248114114

9230933206

9934163008

1208092560

1910991516

9830106015

9248093413

6445712794

2685299126

1285644329

6670349013

1784711811

6420303226

6677367766

5285855545

2240644464

1475555514

1789081080

5780448890

1090770009

6779586150

6685785718

6779590758

6479567990

1739064424

8013740268

5229717947

9013989801

8003783936

5003750000

8163733618

5019151015

9942020090

1200911127

9363633426

2269221269

3161343461

7299777929

4350293421

3516840426

8080327266

4577193946

8617475243

9449998497

8977799788

5667571365

6784997480

0999278485

3177379187

0361309198

9930198487

9210303164

## The puzzle

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

6716160849

6326352622

9721184007

6781127436

1326131363

6186383688

6787485767

6501414615

9463446344

9319990413

3003332073

2243117623

9119917994

1647012294

6089690426

8620120013

2383637094

6326590073

7392693697

1147859391

5171019041

6249650092

4030993042

0780080076

7562557291

3933989391

0092210297

1118116889

1716066107

2493349723

3734773641

5775219347

6784866121

1856510191

0743463193

6327746685

9486703381

3988704780

1743648054

6238747092

7517557757

6246666604

5735853578

1988389118

3453753445

5894956217

7526478771

1020676671

4312056707

7716771657

4222265224

5100058601

7766076070

0668666707

5382135135

7892835131

5884473435

8249693131

5555555155

7211333132

9138198631

5594553495

8562727568

9516232089

9704436911

1774969306

1684147312

9606990406

9586189866

3769479666

2279927929

1754227727

3248323224

7607107607

6430246443

9718771718

3218364704

3717258629

9730959529

5648263320

6257918220

6859916191

8599004335

8791624067

8759967114

1781991197

8799679679

6199019169

6552002554

9594994949

1194999541

8381118366

7348747987

7171196731

0729016581

6754997580

5753297637

8782099587

9097597782

3649403429

1836092033

5437273829

3718292476

6769990826

9877872899

7227972779

4330403534

4346463423

7375745072

5321154684

7422343797

0114540384

0911710197

7187317933

5679169166

5414515445

2322032223

4617004657

3910903990

0439244292

1129599525

1429564014

1815577345

0117566300

1127570897

3915236445

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