- June 2019
- September 2018
- May 2018
- December 2017
- April 2017
- June 2016
- February 2016
- November 2015
- January 2015
- August 2014
- July 2014
- May 2014
- March 2014
- February 2014
- January 2014
- November 2013
- August 2013
- June 2013
- May 2013
- April 2013
- March 2013
- February 2013
- December 2012
- November 2012
- September 2012
- June 2012
- April 2012
- March 2012
- February 2012
- January 2012
- December 2011
- November 2011
- September 2011
- July 2011
- June 2011
- May 2011
- March 2011
- January 2011
- October 2010
- June 2010
- May 2010
- April 2010
- March 2010
- February 2010
- January 2010
- December 2009
- September 2009
- July 2009
- June 2009
- May 2009
- March 2009
- September 2008
- April 2008
- December 2007
- June 2007
- June 2005
- September 2004
- May 2002
- October 2001
- August 2001

# 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:

1760731338

8693234357

0410240370

1549632650

3394334938

0244262340

3670131670

7747646477

1558512655

6234556564

9795077759

4510650166

1884118181

5334545596

4514642896

9385177344

1384561666

4345420419

8234410121

5264749280

5564524492

3275385641

5578777575

5335355333

3764575757

8434228322

5206400403

6904174969

0975719539

4028474067

5399072007

1515114517

3662822863

5569275026

7717919907

8881110989

3853610487

3174913382

6963513367

9943854387

8596554984

5065710567

3103200312

7826664827

8833443488

2019990012

3999434399

6444143176

7972797127

0700439119

3841938122

6605499077

5587439379

4704574026

1330623061

3337733674

5383563255

9779778193

5403273691

1402460793

7735824279

5854203773

8465503789

5314637722

0797839316

8350239322

1914298126

2632338326

7772294722

9139239122

9436139341

1007107717

5346764436

7020101201

9668688666

4906333466

5306786504

4060195469

9600647088

9976153040

9060790181

3313777313

0843748738

9096361006

2598399535

3598782845

9548760093

3318330410

2393368493

3590322107

3309720129

8355755807

5818326986

5348963007

3818778818

5313953991

6144334861

8549888944

8755355578

0308114808

6375735901

9275145161

9301129276

1278171183

0905101005

0309230039

6561766617

9575889595

4937224599

1559556037

4514209688

4137547276

4950777715

4314224444

6157222721

8533538535

1513813353

8260734668

6408732890

8990184881

1736630190

0990934890

1100630161

8690866208

3663646637

2278882972

## The puzzle

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

7878030887

6661686951

3999449379

2425595125

6524836878

5363934155

6959780361

6349449851

5010295174

8195732665

0790553360

7516794358

5730588123

0136515005

8024444044

7799662797

5918789179

8550333558

0003903499

8087040837

9989898991

7711777121

7373077139

3498157431

3500540929

3115890427

1300998199

1266962126

9376878899

5976059475

4392595429

4076520364

9316507707

1262966832

4014994662

1346596532

9411101545

5858133815

5526595620

3637117613

0617817615

8744061845

1073705620

2044225615

9694891643

5016406011

0824948872

4807686840

6104511160

7804900980

7716467300

6016552560

4806921359

0819604144

9281298122

2882222885

3122212235

1207110627

1249418297

2515047892

6998324625

1723412632

7437012832

2248826582

5434553234

0999909987

0315331015

1452233072

4704602934

6593049914

9123831014

9700839974

8277424877

0500556660

1265642165

6674719764

7599652664

8423794860

9631794890

5693924767

7075916767

5555555571

2006665402

6988689926

3794793477

3789490441

3294113871

6589159541

7161168476

9171395476

5222318494

1631172860

8431855082

8379320342

1922391329

7351251550

8473838883

5336836353

8239112293

8834114519

7754160119

6628414189

3709410349

1101111109

4264610246

6676662657

1394934919

4888860388

0263305237

2277729767

9933909593

1666176616

6138875226

2500929515

4278149213

3105976636

4966776566

6686906998

3190229073

4545524540

9111159191

4220279970

9975679991

4443774181

3153729190

2468854932

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