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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:

0113910311

5602350245

3990209902

2775555577

5815925616

5620936062

5902282397

5917933403

5610207935

2187928197

4745441759

6788817786

2303332200

9311237837

4665817799

7429128307

9428621786

9944621830

8075901191

0405435111

9574331973

4734216317

3152351323

6111116911

6232332473

6115665157

9929939992

9728917048

6070801112

0941676912

7635276903

4010771403

3343376983

2771216742

3180808138

8067867018

0791569414

0427345984

2722584322

2871969354

6897336789

7429077745

2921511922

0691880108

1772977779

3619219393

6767066766

9848849884

7851517576

9719541313

3817235579

3641272536

2831597283

9858880633

4690349633

5637676785

4706640660

7859157877

4890122597

5626366587

4036112908

4159694166

4199667601

0123464670

0504909890

0834989191

4885079695

9292572295

9632169321

0151151613

7781887170

8088008895

8396996969

8186481118

8040100880

6845334486

8840964583

8285330815

0040158289

8396749105

8296872437

3026099748

9723029827

5849137923

4437277840

6427776427

8272227908

3331333813

8141881854

4084779740

6066960596

1671873861

0044070420

8111554167

8456058197

1085273472

2454360461

1455179120

2158660127

1433544954

3121712111

1290292929

2673733227

1373501401

4625706310

1223220447

1223585333

8493591796

1881116831

2295697262

5950995950

6666997663

6172210903

0282397603

7346595960

8403897971

5941897953

0599595905

2227557276

8111111858

2590994560

9865494270

9551355230

4829715970

8810097575

5488954878

## The puzzle

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

4103244320

7219379370

2696999629

0796176760

4296965938

4296165211

4786093451

0383624960

2796320391

2301041734

9647890233

4207394234

5192890237

4394994234

9099090690

9113959331

8303700437

1323441233

3838838848

2247228345

5350555035

2399338299

9034058399

8699828735

2244638542

5526858039

4503235398

5738252887

4966158611

7267770139

7516672186

7150750517

8698782679

4448648886

7131377133

1791116191

6225222252

3258838580

6295496994

5308350303

3223381830

3298963828

3225859662

6323071704

3325822236

3535135333

8830707188

9861469168

6759373653

3752722240

1861467943

2851354409

9751126485

8865120994

3534738334

8279979278

0613404006

8845959588

0739542112

0239996156

0899457339

0503545530

0539592380

6674829402

1889208379

0005508819

1196215429

1989918119

3924704729

5535315352

6093029306

0740202470

8674983531

4787272471

7125773971

3339073471

5576972592

7447343270

7913339171

5991185931

6614610466

7100007719

1114994711

8152105182

2797719277

9145815241

8966504277

6290317342

4894904342

7814508714

0830036080

5721552027

2264408462

2409990442

5336290022

5599096062

6230972860

3983136882

7660190020

5797955939

1596212256

5236723367

1210111111

1716744230

1204774682

6906117428

5716837525

1906233082

8595243658

8503685111

3063360155

1807303888

7797333777

7033663370

3507152005

1825252128

8065454845

6636336469

3099319300

1217010721

8044776804

3933478804

4135819841

5396619075

2710916465

1656616874

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