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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:

0021057083

8478697027

8235596913

6283851813

3875575823

7866676680

6053557026

1771171017

1988997918

5071252700

5485585544

7268562878

2562959256

8068964915

7878939608

5233624434

5462513924

8432543383

4185946604

8346622648

1498165644

3357655902

2688552608

5541945941

8222285122

5669666955

2744747344

3675563572

8020423804

2296999629

8729758793

7422099814

4552793173

4519827512

9025093509

1616967929

9917513018

9799882180

8772386060

0709381098

0979599597

9207770779

8382323983

3799339939

4117314744

5699559566

8808660894

2487467421

3733731273

7270631862

0132686856

3813859424

7667201851

0279566866

0291289212

4471474411

4447040907

0600116040

1672879941

3447680917

0221474719

4707440942

9918084201

8586056608

9702596750

3131338312

7773332785

8508696718

0000256358

3766159758

2580808680

8735338705

9275083872

4075415683

1276424035

9576305526

9055393995

4576044057

1174041147

4201402210

9246848344

8586448868

6357073357

8962062019

4909119990

8707143235

9527119030

8366469926

8719086629

8359114699

4044449044

2222520532

2222492242

8555555869

0672495022

8163035632

9719650862

5945540222

2126630062

4534222244

0834114404

6029889982

5530730505

5537700955

5639659415

4837792236

0537127113

8810247121

6986939917

6904944810

9987993671

2494947641

2488998988

6044774767

1996898699

6955299595

9600994996

0499140499

9753175157

2662666662

7121911411

2792167216

7153170459

0691113392

5460693901

0629998287

## The puzzle

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

7535881878

4707777077

1997517191

9632333232

1202721974

4292378106

1231730608

1235884353

7737572486

4466464416

1884410481

5250090598

0030533650

6813231420

0277460315

5467931510

6116491521

9073190426

2638222222

5739993495

7904117977

3506995366

9606908686

5738975310

7004294973

3639138923

9909977893

2428180241

7647007046

1157171271

8111198168

0792617176

5479905244

2013018248

8130018246

5057577541

5506863842

5006178398

2225485581

5446128504

1146111614

7226171121

5006360230

5432112521

2505405445

6776648424

6372644419

8376497690

6676922073

2151955511

8072428408

6606666666

6372632122

7306430060

4993324131

7869135750

4023740352

7899740973

3922791793

7969767766

7803888870

6422442464

4093343440

3219359152

3220355539

5920361236

5370520071

3912533191

3297572997

4200340304

7322373379

5979997977

5862370875

8569188973

0564434707

0855104067

6595196163

6852485845

8864384348

0636766776

5262452265

3443334893

5162515128

2878887882

3303370039

3624630049

0816389889

6105985828

7014600889

5443770043

4467464446

5319449951

2820111290

0785578757

4817563170

2820439702

5367928447

5085433008

5737499124

1458246041

4400245059

0049695615

0985896013

7573175129

4804484011

2525247625

0596096005

6767666753

0890330789

6268888620

0120771220

1127116102

8641231620

2027070620

3567780720

7910406280

0240728780

4749948603

6744669854

9029937854

8645818551

0383330820

3111049601

4118861814

5535838565

1175717851

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