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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:

8281128012

3344349533

2551526559

3005550310

1230653012

9710329513

6350770033

4491946063

2886120639

9357518860

2956303105

3859376249

9380304647

9343595333

2380000830

2557572505

3589993595

7956397666

1004770751

1498110785

2231640784

8570895783

7289979284

3340340371

0820282703

8585598755

6267295622

9687697186

8909974009

0111104411

2300338302

4112675006

7252874609

6734694081

0178495001

5758374136

5021958589

9334439083

6504569553

1596831583

4890559084

3444464483

9993449699

1155151581

1311831853

1040306143

0676567676

8692666696

1310933091

0370903696

1310627771

1375517105

8646644455

0945333724

2987485068

5488644470

5216687834

3487703803

2388733723

1086461184

4209099300

5416615565

3307333373

7137371603

9799149179

7999274992

8013130881

5817634608

6431671982

4104971642

6080839144

3443370643

9577706431

4521737161

4127767129

3527947493

5427995942

4171714714

3524739552

8991717199

9524944922

5895046819

3835657605

1832604691

9698762897

8631736833

9892002809

1635735155

3250603585

5898688558

7733443703

0221707182

7745702757

0949939409

8669637702

4310839751

2538432789

3242509403

6698533189

7733363777

4655165814

5055840855

6667376366

1358875957

4467243865

8782740854

8287877756

8896861864

1711772061

9117897138

5557557655

9505950909

6793890069

3278852165

7205050008

3148592695

5663690629

3291525535

9075000007

5160851550

0941712400

7325766492

0221842775

3974768446

7295808198

2321079656

## The puzzle

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

6686377863

0058905958

0082072820

9010910299

3342477823

6571677923

9581315829

4839102998

4053175954

5188585488

7077227702

8664328436

5355355623

6913458432

8252427338

3645125723

3130858733

7503360802

2220554538

9437596971

5917038927

3919690608

3997937997

8529894528

6777656771

8020650806

6656818635

2506222205

8751478521

6826482486

6638776833

6606741324

8801422777

6508292461

6153908755

8856861355

4159826606

3781138169

0771138807

9681748820

9271777112

8787668768

0155211215

4769890987

8672162172

9949999460

9008990089

1373571530

6654354936

6546670599

7488499486

2216729590

4695824030

4444629289

0392159196

5445707519

6444770416

0445105688

0185355805

6319419164

6844161664

3342244843

1490790990

2888020888

1600370361

1611191156

0750990427

6954890366

6364691327

1762221360

1308294668

7755991361

2622682286

9688498468

4746434679

2514315436

2314830276

1082138469

8829882488

3925185961

3740838479

6772527677

0040540500

2870580208

1661911196

6640949982

3672523541

0661549549

2670587344

6770444002

9303403348

3196776917

0432244402

2878117822

9493124656

2498422590

2158126920

9392681883

3496479767

1466716488

6738226778

3868926184

5202216187

8448114187

7777616777

0144026104

0000000480

4230332468

5104977834

2100220823

4903396415

3512891884

5599393825

8847171883

7776176118

7734497438

4111421144

2100301032

9892639698

4645545460

0661551806

4987459692

2604126692

6495541568

4517705835

8804451865

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