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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:

6957154529

0077109676

8784804616

5482096079

9969999626

7555951579

6248226687

9901904019

2888988029

0934884888

9980399999

8557055358

0384334383

8337383404

9984046902

0987808800

9587095189

3357329498

7979898878

2112187211

2427440742

1779912799

2481098819

0955612811

4893618747

6941790771

8064408717

4745337254

3069636000

9925459454

0972999992

0925342275

9968474204

9045774571

0028607132

3925488658

0434438839

7533519137

9534144564

0613940281

0139111191

0654454440

7417971277

5531955519

9623692262

1713442078

3032816067

4989616766

1080630777

0081118066

4776435047

2625572566

5171710157

6877786778

7094975749

6063326300

3101203312

4136335146

6049636712

2054105326

5417905746

2896036149

8327835709

6266464432

8304843088

4406458464

9877970987

1544473497

9188390984

8606050969

5090794498

5077653432

4147906480

4962809830

5980986260

4127983540

4982999989

5980090550

8189888981

8827272278

3162003668

7773737277

5567476645

9299469430

2522150126

1385857134

7679176136

0233079424

2232160372

5096867420

5516824430

5463218362

3767012758

0466924639

0596790772

2667007776

3413222434

5743935344

3966896839

8792474909

0706650951

3396258806

4140499991

8474774881

0090009309

1959151991

9692998921

5979575956

7977077799

3108031050

3938433483

9752759277

3958727746

6987746630

7788457412

9937013383

9757425197

0754757404

6826464862

2057757727

2384778892

2054725309

2774758616

2274754899

3958459798

2278788997

## The puzzle

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

9997947909

2290990929

4411114141

3404550134

1213450929

7769914941

5405640130

5816064159

8399814121

5631066550

5429094759

2063161061

3428773332

5467787877

3459490443

3028643264

5633118713

5468450570

2966662666

6239629602

5451010005

9248994242

6238162813

9456981214

6445631042

2459230496

2438692693

3975991719

3125968746

8425625669

3175943538

3039993330

0345950453

0127620621

7575257725

8919495488

0996095048

0186701136

0018727824

0185508234

6968393688

0036560403

0189701788

9141719741

8195018190

5674776757

8731387887

7827676628

5754119145

8724501792

9657627933

7734789201

8657924697

7624776417

7655839368

9114419347

8109741048

8958499066

8181311368

4461651046

6373747063

1218119217

9485899548

3250205528

5336636633

9195595995

7149719797

7390548984

3140714197

0476533170

0275252270

9136542092

3923923928

7280070398

1222123121

5532532568

1863833931

5394650323

1615073198

6342225128

0797270323

0877200778

9033030339

7473573344

2260775277

7030723824

7877049237

8205213990

2465570607

0663611792

2363366503

8777798727

4054430458

3743779347

1374279442

4929670348

2467530708

0792675503

7666199747

6691449944

8360663630

6694339966

5900759795

6694782191

6660492947

5991492201

7765477953

8796482889

4888999982

3590990999

2277447424

5807558858

3897909185

5027973710

4278465118

2297901010

2207927022

0857491420

2158373250

4000783050

9881673400

0922772209

1581181358

2484323421

9990091090

2390093200

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