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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:

0618600688

1028112138

9838293288

3489553399

9438128717

9819582606

1488462407

0029868915

9928280935

6885005558

0122101111

1661661666

9265397533

0153323802

1282344033

1821571894

6264314666

1451121703

8082520337

3884543158

0027903255

1907890307

2898390328

7474084107

9333443356

0202202225

2782223287

1926431802

3086365725

1946377768

1986387579

8000770870

6746867874

6926496664

1986396816

1588858854

3411131431

8168865881

3333331233

3718713307

7187411031

6599371001

8307415887

3451472289

8155232237

8404448490

3937093380

5244494245

1154554154

9675434373

5933044260

9975053385

9964894180

0971494253

5250131653

7034281273

0942384055

4072656656

3112351153

7666764657

6567758076

2756776225

1311181341

5539455024

5209019062

7277929938

7799983111

8237338723

7507655057

7879987979

3079399773

5796477374

7063773152

5016274832

9688287668

8309920871

5009990000

7689228998

3783273777

8318738898

9066066006

3386546074

3149669276

1358694157

8682363009

8646555866

2933333422

1758888858

3386633683

8162066881

5808153531

7862188449

5552678416

1888164912

7882177122

5057650057

2566969620

1622116111

8818333138

4454665590

5903361415

3573476772

0131076770

7665775685

6776661575

2221112212

6666666717

8479086490

3651550763

2805242013

0617086013

4875251213

0337337233

1668186016

7237255723

1140242018

4141641061

1164725934

4564738767

5927969876

0131520960

1261712676

1734732147

0123530011

4561366431

5147975911

## The puzzle

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

3646345623

4447460445

0101757120

5355337657

7193437447

5406467457

9900255550

7670450621

4789057623

1754420427

7785130797

3249200416

8676631021

1351511459

7097980797

6460006941

0122220126

3237230027

0909464094

5539395553

6977906794

3521315683

3169856401

1855256703

4315866453

4984591053

4393304393

8495833818

1348415880

0919239118

2632852128

2003112089

1858252810

8183535831

2226215622

9481449128

1181081102

0100991200

2436437241

7470775407

8420471200

6319987147

7477735247

3769936207

0808176192

2699534571

5840654190

8073191099

6437837140

1513195173

6033036030

3333324743

1151111501

6656667799

7401111011

0033800838

4784585445

6958753899

4008784475

6434317206

7705502267

7081534894

9755755814

5552686205

9687967948

8885989544

3673113736

1753013935

8555264749

7251226235

7674069344

0284869702

1259555032

0755198516

1339103737

2739345259

8736376363

0215102112

1850854805

2299929999

7735553735

9992595987

9991991926

5225552553

7711775141

7925292953

2358491151

0732592121

4402975947

9001194521

1014411400

9337379232

4522224321

9525555952

3345071953

7940919932

9968015223

4047574802

0458175902

6499890320

5408511625

9667076838

5757725869

9559159191

5597055776

6468584486

3707733370

6002862600

8260173245

5612570818

9353843849

6668070814

3742973249

4464142614

8049450840

1990770917

0077004978

4242215151

8216619730

5258999725

8026013725

4353993125

9119319331

0099669720

1551511252

3334334725

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