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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:

8216648841

4556633702

7400932962

2362452905

7097710597

4848848842

2257022705

3976933969

4122452941

2996326939

2124421824

4474567345

4196994891

7895014845

6984826954

9105866831

1335621324

8271221891

3845817258

4645826201

3539817186

3835763277

3445777443

5871875855

3632836363

5187475157

4509749752

3389558998

7390690699

4452124354

3554555553

4398182650

3398530889

7498884321

2058594519

4458531430

3749947799

4289949298

8253782357

1192191920

3180164430

8299782105

3747991351

1792716061

4143190373

2012821761

9534441587

3635325881

1796855563

9535535591

3263645263

2357825783

5772557287

9151711587

3943199288

9760299270

0273233098

1012019280

2878772278

9899898098

2283283252

1383093280

7919919798

0660767071

7933339073

3979239231

9858952889

8581859271

7708957278

3147162775

4784960231

9565030875

7228425321

7478748067

8180492763

3128589696

5121152511

3282424248

8778787817

7028002707

7410515770

9932244012

7454408160

9885238120

4286634820

5559754873

2432334260

1333749317

8051568150

2202404222

0040400044

1203513725

8978779984

1122110266

9021070334

6913803164

2046319734

2699203935

1548410766

9404000494

8303488336

1020420414

7612556122

1622582185

7400455751

8398429105

8404863112

1603263157

7240234712

7375631283

4036030574

8346076773

6363736777

8888871887

7939395273

1194434114

0260602562

0113846490

2641177929

2349508339

6184946146

2189511558

4343444444

6154242220

6641864144

0618901688

## The puzzle

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

8505000508

7804048807

8263121278

3570570573

7260740654

7065033929

8239068905

7273544790

0825123330

3137930868

6332085398

5877233382

9245259462

8888150182

4444883464

6599569456

8376370328

8890336890

2934580822

1281881302

7647364902

4045270439

3370373307

3035060937

2700004729

8478587452

1228171822

7803608866

4376133633

8122787181

7464996663

9364905602

4344723945

9367608145

7306653974

7863755570

3401024054

6441544810

3406317994

3486961722

6891313931

7404947400

6408505346

0608500600

3386060006

4189731373

1317099321

2761698923

5795692162

7377151367

2293998923

7252252774

7655666152

9912009121

7046731870

0145574690

7456405086

7066567128

3325353333

7556575555

0065400405

7106518010

0045704000

2330355752

1320775401

2362728183

3862786184

8890798980

3020332323

3332823833

2662622266

1409010405

6810283407

6513185615

6416151586

6276102309

5578175758

6816216226

6430164300

9601119117

9253252929

1174625299

3552635966

7198897925

3801693967

1266113266

9562595260

2612121927

7717717077

2992935299

0599345716

8594122271

5139646771

2844635816

4334334371

2262222216

1114747713

6146146216

2684325834

0527521837

0921341723

0924538583

6527164669

6975199575

0579353799

6568556856

0521813552

2127972992

9700663621

3105560550

0875860952

8694254550

5555555953

5090500560

2223362132

4764664657

5257723571

6688482164

4601031604

6191155491

7713557321

5425651121

4229630391

7625482324

7962532301

9092281364

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