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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:

3105515230

8657184716

0762226570

6677337336

2109615470

2954337336

3503610216

1982537736

5144787236

8585558600

4740952265

4038860260

3556890660

1075775601

6202692606

0716160167

6828888268

2295250280

0155305628

5456667762

8276102829

6633017762

3600550625

8882882282

7502005702

7699367369

1883615368

0140564027

1775078225

7530724053

8909454055

5159555015

2228728277

8775558753

2420564025

1216611126

4044000464

0919391930

5103306132

7224773422

5206690132

5949176434

9851450463

4587451133

1008700936

7721424597

2027388223

5014465235

6269122134

2067372736

4511114161

7123442427

6289622888

4704848074

4303558229

0717968234

7882451227

3041499247

7525151227

4822598254

6211469241

5397954379

6234424593

8529831278

8640515225

8724886480

1649705284

8684779747

6326882622

3619816896

1746541545

8540004004

7767764775

2332213298

7793999377

1676776964

1118899375

0104744998

4848039537

6601516975

9743116974

6314437426

6060076000

7565556857

7075575570

3805236850

8297976097

2730276470

9523576855

0959977877

1598007661

4608524877

1398580825

4098982052

0578558058

4678778780

4018040018

4309993039

1198819988

8898012800

7555555567

1244112404

5388558834

3593218530

4049852804

1659815560

0773354860

3908358804

3476868471

3622312535

3672481679

0670585998

0552550255

6476366766

9676886896

3402430044

8600300396

5794393116

2609873118

8503983114

8735217146

3316313416

2331823828

4441487114

1411112141

1900096106

## The puzzle

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

8829770279

2894888899

8170681677

2436773776

2404745079

9620732334

2839891170

8640750119

9636847872

5647837468

9251951912

3200053020

5225556562

1800295262

9020655960

2166796220

2355331828

8708853022

1587088800

8109056411

9334868971

1303057870

9649996478

7947667987

9959558905

8788188871

7076696710

8699334385

3099111355

6777374193

6754705217

6704770478

3099339330

3619369131

9757888787

8673163167

8515408502

0565775083

0804760573

8544760980

4832738884

0514251280

8575777787

8542452248

8609209998

4880104681

0940949930

2192711722

5222315203

9151211903

0262519222

2448901209

9419945732

6466045983

5435276430

2675680430

1453410411

3089870430

7799776389

1311130712

3133118434

8000080478

7187770610

0990289742

0635215131

0995156226

0505943927

3050113335

0900339006

1635226556

8599229999

0630900099

7005002058

0181111008

5001056107

3241531254

3820651057

8562892104

6347731057

8983892607

3444109003

0638163906

8744123702

0143153816

9613653042

3230353302

3502423046

2748726748

6559353916

6051161052

9494985949

1574714750

8913789173

5955555597

5064615194

4568314973

7022525771

9191785147

2139885749

2983828389

6839288693

2359637253

7968177619

6987540741

6968198456

6973665885

2872618231

5933878118

1530590105

0666686680

9799040987

5111751736

4163050705

9178380137

5006886105

1406480780

1100071980

0455945638

7435299651

0387795838

5806499634

1101919031

3939899938

7995597858

3722925937

4274175614

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