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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:

5423788707

1160574708

2169078872

1869105618

1163111696

1369001001

2769779729

5120250220

9810555890

7495671451

6356354355

9123141465

8966450428

5582152821

4181881435

6464444268

0588850888

5691551359

4074904444

3410110433

6553753765

3032530903

3532780584

9434214837

6583932957

3553511786

3072716434

6649886466

4790777472

2659009969

0464994446

2559948259

5655803681

5050038395

0649974326

2559805318

7408759080

3572559097

1661379900

9846493355

4156155314

9999099097

9696089065

5500555250

8333973984

9199106921

1299911269

1091719270

1119331132

2411016239

2863068222

4993731279

8156136990

6380839172

5080558203

0593920953

1656156816

1113131653

7235831816

7550256926

3511089653

7888780916

7262359653

9607701501

8902926029

3323191054

9306162378

3900993909

8822778822

8847224784

6624646242

9366136561

7222227532

7977677261

0029999520

3107371301

4387897231

5052439861

8580897282

0020787381

6631397828

0791306190

9768632447

1001632809

2301367074

0098998999

5601366351

9369592699

2778682872

9214442124

0735431098

4896815098

1373115021

4954416028

0021911029

6433935494

2884002948

0300006083

5446675654

0806828034

3157771119

4507963217

9873945516

9297797772

4106400414

0174441474

3853933338

4312812449

9259556319

9752059564

1775996398

0296564195

7554575255

9725277227

0812901819

1296366332

9419094949

7152913290

8768696233

4752491896

8758184612

0912332933

4459141451

7893683959

4968499448

8756969955

## The puzzle

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

6774385547

1687245186

7477450852

0837324122

6833116116

7689396693

0777274727

1274441174

1797371773

4485198743

8425776242

7575400693

3580147438

4525994451

8473434437

6483484466

7100101177

3875273327

2432711257

6930146143

9737151398

2088787729

6030996650

2462224664

9182728779

9918111119

6697366376

7224744470

0925454594

9493229332

4002552400

0902568887

7094537923

7005227437

9474551411

4044292045

9819901892

3778784537

1447448974

1331331183

2039038837

8658741593

6995881597

8319589981

1852281813

0550544563

9877751064

0840594459

0500300784

4400770707

9370404709

0550700050

8507581507

5862353655

5828728252

7367262673

6713771173

7441175411

7311726133

7723769286

7313215648

5365155208

7317638314

1333533113

9469499249

5886255558

9046394603

1488587037

9339484145

9786475493

9068555570

9246400089

2967779692

0164504047

9818188888

6735753757

6835728679

0934713833

2764797594

2114159101

0267176333

4180720169

5149670163

7732920181

8166270685

2512152199

6311621666

5518770185

6650550265

2222124521

8084985904

0860550568

2420409244

2172112379

2736451508

5571742948

0089225238

9231380979

8615011369

0022206242

6676797766

9599797995

1046197104

9096296765

5889596604

7442306946

8045207945

2238637765

9233993239

7507575805

1111030115

3555531503

2726237239

9805535513

0228965509

3705633709

2710335813

1402422384

0065320548

9746596304

6268451346

6955996580

3423372340

6151851786

4244423848

4820420304

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