- 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:

5618230760

0927239341

9372976948

6978185452

6372372336

2416111144

0657200563

0227970022

9978079797

0117455848

4584685336

7522788830

5265275376

2257572652

3733353376

5226425346

8817887828

8232888230

2680531968

2336533249

5072371055

8332126986

5212512517

8370770038

8038181383

0482300304

2176171617

9996494266

9943745833

5946005739

9943984722

2946999992

9947790999

9033609966

5893285525

9153451591

4444464544

0022990022

3380333308

6768978690

1415438520

2336164429

0104178448

2263973644

1818437349

4484649844

0017500705

2942492242

3878939888

2912983943

0987590411

3448818048

2417872963

3419503754

9887988987

6715919571

9741444974

1906397696

9885320193

1886490516

9912990286

6686961429

9907316575

2991222298

1314141431

3693469693

6999779999

6939149983

2711439840

2399763180

2934762513

2691126441

1499552221

2409515625

2433078042

2411341878

8812518828

2499399936

3903505353

2431231134

1221022211

8286776832

7030703037

4103331333

8263738778

4238380868

8036726473

7266777539

3968811429

4280713545

0161666606

7292323727

7712477114

5602356282

0392345307

0302467712

7198339913

8112373116

8612331501

0414604001

6147074764

1116311211

2129552512

0176527147

0149676688

0446529302

3441582718

1427573472

6937298994

8103319165

1707311954

8880361206

1180318811

8781818888

2903222223

6902330050

8837388338

2590733362

2190754308

7699733057

5195582286

2643776776

7190670176

2199591751

5565454456

7690800977

## The puzzle

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

7656565667

1204084201

1130313313

3893398063

2249454663

4759283363

3235185613

5300975371

0143964110

5249652465

4035001113

0123481163

1739671316

5832552385

3934639446

7919371369

5444554115

2243202163

2233335128

2597112905

3393595393

6003330621

0559216628

5747735328

5598536908

8843216928

8359911945

4705031399

2781159519

2710753121

7708436193

1114939311

3530336503

6165156170

1191937129

5595533597

7918591857

9055595505

3817073870

8088535580

3372271550

5633701585

3469031507

2946501500

7586981200

2655943372

7271642978

2277416182

7328416942

3334333343

8382802348

9779117987

4777040772

9766446192

3932532342

4694444966

4921649441

7884554484

3734549429

4681535963

4429443952

3782691698

7831410255

3048924105

4258644109

1978117525

5279964866

3479999979

4953995499

1279179113

5028665252

1048111181

4297778464

8004756037

3922874060

2957074498

1747374037

4824226804

8080808498

9474477094

6655555666

3360811229

2501203447

8360310561

1566520626

8364138161

1301515353

2528225222

3660339366

3236836336

7164367473

1963396919

7894497779

9185399354

7964909208

4984382260

7163347498

7923305488

9184487441

9290707952

5165773615

2823226833

8447773474

6541076471

2110879635

4368073574

8377404873

6341223615

9009000919

7872802785

9918975988

3677737466

1755630469

1696700989

3311202484

0909432184

2014305974

0009220940

1214944199

2920290226

4341331114

9016230350

0949734158

0428520756

2087591124

5967244949

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