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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:

1505155018

8363322863

2637575634

5866550668

9454852238

5021905034

8554022863

7807852633

0436755318

4374747443

7059307355

8751351873

0692792971

4379362279

7699318452

0089749851

0792099914

8359386279

0777370773

6946962989

3664664763

5050158031

6825652060

4312262071

3307500969

7185761914

2242100083

1718671896

6768872866

0703773070

9911339144

5835631846

2433779876

4589971064

9551231920

3349902864

1402952797

6529492711

0639462782

3275874411

5929559212

6227792777

0007077091

4478462487

7171474511

5914171672

5970709796

4570125831

2570725699

2609792977

2574554592

8920111988

5866766655

6617116116

7520777200

2584152214

6226366626

3130735333

6120165109

3950770734

3220399700

2580117003

7231730050

3413262783

1060062626

5969992088

7953872028

9557599725

1180181733

0626862028

9006706679

8161871688

4570142023

0672743941

0833511202

4580545924

0887777887

5862265212

3574575334

3237979397

4620111426

4446746012

3858942262

3534333235

0857520949

0548770040

8817588787

0884904189

3858088058

4436863486

0040552310

6200744241

8028474634

8000785179

6278178287

8454485884

6456466644

0020700070

7001511780

5454630982

5955618484

5634331937

5455327437

1469314164

8667286682

1504941809

5834658483

2955655259

6153881861

7616966966

4847333474

5284555655

4116381215

4158979798

4240566307

6213909859

6614839878

4222424224

6776756367

6926069280

0888998083

6475899323

2071798227

9305368297

8458564267

1472694764

## The puzzle

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

4208148688

1318418411

0903909990

7305135313

0208721960

0248130087

1905411772

1303257090

1548146223

7370565078

6710204826

3313929569

2350960551

3316113161

3750455524

7563995356

6122616666

2773575377

7614481627

0682659267

0622722364

0614124116

7682772767

3675172657

7664564667

0924840022

3419431994

4444494345

9379993739

3434393194

8142993824

9957893894

1497993771

4935294334

3557223164

2323724734

7066748752

7086357394

1984753094

8565413392

2298758792

1281141722

5733517354

6868846358

5309153190

0078974405

8735096756

3033962567

5703960321

6065959890

8933333833

3108232380

0768086880

5735737735

5437654355

1834540533

2298008282

9896111681

5436543683

2886695267

2036110878

1837694482

1418627395

5626875694

1027296970

5328866489

1509507582

7208552508

5007117575

4526868683

1374414434

8629496629

3633881606

2145183273

2499887095

9439561320

2529596592

9496099049

6135961361

5243852282

3649769499

9852989289

0225924590

5050356013

1911111494

2210416913

4512218291

3688056481

3350654019

9001921990

0181585326

1092178768

1541676728

9397876726

3333376333

7060770764

3222772426

6127686721

0007708758

9179179199

5876262565

0118901019

7877977178

7116186078

9857256447

8818205822

9118219942

7857206779

3098908516

9147801596

7239111397

0048017556

1111111158

7777700377

9090577590

2111111297

1403603516

7438448722

4240404462

3874228374

7696796437

5760498467

0978228332

5994764367

4728128374

6048226476

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