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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:

0872690162

1346641462

9031346163

8214016863

8749191848

4244141452

6000000766

0663690163

3144616343

9209640686

9509547148

9239762050

8101704974

3160991906

7202972722

6531651555

8309600893

9100707980

8884782010

0826782619

5063886089

5578612019

1013316031

7280882087

1649881569

6262122619

0344064063

3952775153

6422645779

9765063559

1678211157

1911111579

7009740747

2527775273

8288832158

7774664117

6012418000

1078300008

3696999633

0347555470

3697943340

6978483940

3378974374

3017494369

9076571857

1134014500

6192869129

5492696659

1155555155

1192580114

1152653855

5455069476

1197007724

9252724398

3099308631

9684333775

6550151328

9597344850

6056330236

3387188333

0699290690

9594854554

0750100001

2270084372

0569615674

0636456661

7693056271

9999559697

6622986298

6626264272

8588656381

1545445464

4802598218

3495196247

7577896548

9778696824

7740577548

9118890118

6434626364

7662276227

8668888869

8210285086

8780748275

6279953212

8781966981

2771972777

8036808082

9210210129

5440755754

6780968686

1694961944

4504845800

2902302222

8549994298

2939369450

4909877408

8699530369

8295964192

4535977677

9847808476

4734508717

0967284437

6712679757

6627979612

3377743377

8500708757

3435586435

8379878836

8336663688

2848191482

7755575759

5541554141

8145273129

0970671651

5112653749

6977954181

4733595650

5313563135

7323767793

5060010650

2929191823

1878613833

2158310190

2069160653

9591862857

1723067155

## The puzzle

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

7799749387

6767657066

8534113845

9869196013

4763616247

6533259043

8002812580

8355099846

1595642215

1336636031

0926022626

7657957779

1873113711

8337905374

0374028265

1373967093

1957674962

7837038961

4237712437

0730060370

3433333389

0009937509

1416214300

7649117507

9908160980

7529910589

9601333387

7516165116

1187579571

9872888887

0914559019

7127523074

1972560975

9127955898

7114409515

9126505434

0334431433

5880808588

2763132272

1578158111

2754102437

4766418018

1588105807

1688473306

4368100590

2321392555

4777803582

0708910752

6249493588

0359393509

2445454852

8288212882

8009800758

5357110735

9431775224

9731195206

8150383853

9034528983

8631538328

5054100550

9782787279

1910331113

9431119193

7168203778

0490815512

0537835842

6787257402

1772337712

9555815840

4450505545

4004343400

0880050078

3820127646

3213972032

1923713662

8263780853

6022770052

3813553335

8461248461

1920102000

3245255332

0441617854

1394621104

7314823114

0222050804

8358553882

7741717714

5990923409

1473373104

6256260852

8305726865

9018379669

4328053806

2799679815

6673773316

1166976619

0659659605

6666676016

5328343865

2593723542

7302789291

3462412090

0592743106

2562752777

0592229950

3372774733

7003803708

2418444482

5329996503

7444774776

4441475441

8384338481

4187815508

3371736488

9068136803

0908496828

5692918776

6391774706

7164497550

9442271384

8403474950

9927757952

9010794700

5000005500

6636676356

1381151381

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