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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:

4488288429

4469114365

5947947599

2889595528

0709897425

7378984598

3760242398

5803715518

8774489525

3975395039

1148054129

9596022349

5880584744

0138513358

2940882838

1872122118

3085058300

5596339596

4757117155

5385783887

1187511171

8696797927

5159749385

5477573182

8376753939

5675751512

4397870763

3307997730

1118551815

2276636872

9959779591

8175039531

5944990875

5142986592

3955190812

5837867831

6472224672

3531353413

2022228820

3095331550

0687630623

4382938613

1899758673

0358958622

7116051658

4988152354

9986413400

2634174655

2687704153

9984191191

2437774234

4515145951

2926626929

8685465664

7870887392

1191109171

5853880593

5350990395

1299219515

4199809597

9343690597

9132394313

5470592093

4646026840

1100055109

7373473342

1112312463

8662215039

8416476000

8506215149

5902273376

9316922803

8499563628

0316973286

4896155268

9996874629

5526555628

3967663779

8281261282

3766474624

4788764867

1100780710

4252572645

7100110608

9453535459

4574835619

7612735459

2759813858

9100480609

5711875648

0246779200

8019995300

1771141325

1083635335

0755570325

0330335250

7108801787

3374372308

9133999139

0458882887

9899814646

0848655917

9954360455

9843338943

7591272595

0154154455

4448844887

5959855955

9393393999

7526257776

0400000044

5519911659

9510941154

7600092577

0426034321

6373996339

1417972262

1000140400

4374289694

1571230546

0607147216

9531155911

0397333779

1371413311

4004240264

0650111061

## The puzzle

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

7936580379

7239016745

7506972870

3907525986

9956756595

7597009777

1439934593

3206553636

7001570111

4192332899

4562562556

1328131811

5287975977

4122501955

3581516401

2527395247

1598593472

3622270787

5966996952

7844047089

1861119618

1847778417

8246479417

4175997682

9991616427

9247416919

1734668484

8167517817

5570677777

0038008000

6810778388

6210786531

1137476845

1166515573

0870498868

5078671351

1055565055

9179999971

2522528533

7722752277

9622099957

9910059958

3201555853

8743557577

8725159838

1839545626

5244743286

0772225219

5725835049

0351535083

4422430224

5054442540

9149040719

7666627676

5133810775

7753398652

2266322657

2788367641

2281991922

2783323787

0731610656

7068306377

5158885115

4683188146

4199019400

8395668899

8222555822

8290345393

8769134033

6793585303

1295527678

1783153436

4113631141

6465222666

6355757467

4285114512

4865700724

6413116566

6815158716

7115493369

6313144368

5790991975

5149393935

8854664885

3598959588

5114968088

5190360302

3058981452

8818978943

3159963660

4444545472

7717076014

9779303979

3876573365

2798233779

4132503949

4074803474

8078233242

1236976375

6079949407

9059990579

5333675633

8899998964

4955610673

2627770574

1834695673

2672215604

8968073663

0423813511

1532152091

0844952643

0588650061

4022110028

5353353693

1005056041

6661010616

2566252966

9410214705

1304081028

7777988002

5550230478

8440718407

7999494705

0882880872

0886323058

1014131041

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