- 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:

6969669362

0616601266

1119191511

8020590589

3021699212

3097861329

0111240361

2208991567

7388941283

4905859064

0222259674

5942559809

8483639824

5196959476

1331135019

4464444604

7466647860

9266296526

2525895852

1831138411

1999691936

5144554175

5822295175

6123794435

6659290175

8993199075

1960745972

6600012006

5773575534

0353008336

3889993862

7176415536

0990995034

1252818816

6158958332

0882198856

6564406452

6050670556

1133931092

2598590275

7371236560

9914301092

3252400255

2421931291

5931090052

1018434134

6507796375

6067702625

1957700257

6906799066

6061660666

5652002152

1018181111

6257465264

0286788780

4755954545

6648990996

8907199019

8207167102

8657978275

8047750290

6907386525

8947948050

0320730817

4709992385

2386011819

8373694585

3322132512

0877010788

1114141819

8605860885

5429994323

7312810553

2768648795

7389379035

3118366083

9918339131

7736993339

7136666316

2589150895

3362833323

5105548787

0328951647

5607127244

2307908978

2828552625

9107219212

4305000400

5907119001

0305990050

7080820878

1315771137

7455757341

1811518854

8708670817

0103911837

5041077757

1241927171

9023277874

6866716767

1371517335

5855565558

3943594135

7837694755

5414716538

9201697167

9722746158

8300316135

1433343143

3777769687

5193519503

0074779004

1696075003

9101449580

3293843633

3686645644

3433419544

1261977779

1753918800

2431485323

2451140153

8221912212

2251321222

5431135541

1723441241

6778187715

## The puzzle

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

6161665161

7454157174

3434773540

1617777198

0292653561

1544875170

8007805528

0354075151

6288657168

0144836431

4808608550

8965210383

1160614050

4411334181

3368508533

4047730470

6535636351

1050015040

7994388883

7069457099

7290229446

0294365486

0590555940

8994294949

7016407067

3244322442

7229397222

2961299539

2891430815

9897965094

3890103886

5891111199

2391212218

8967161968

9830990339

3172932797

8911972769

1119990068

8555967166

1492943666

5486358335

1791991193

7586161617

8912002020

8155988895

4628968155

8436808187

4987178382

3504898312

7161771650

8053808352

0972570215

5494595154

3883663382

2559885959

5045202555

6305233906

6862776662

6872742138

2355817496

8873281532

5745735993

5705252675

6666656671

5810080751

9977397433

8335358397

8162437301

6728855337

7928398771

5912396351

0639536636

2243323249

7833668763

4242444222

3290337207

1406638249

7581267769

9717423202

4033633283

0753244202

0131931930

4846557486

4446646445

7775577052

3501237452

0209746458

7391686490

0781847958

9387177045

0082920907

2126512156

7555666557

4191999451

5945412554

2549026156

3201898157

4111720157

1792496154

0867173600

8924393993

0539777770

4609333394

0600348321

0860308813

4804671426

0030748441

4877365816

9419239871

2119843589

9379947025

7489927796

9129912219

4685556585

7211211717

2497848378

7349239979

0283592828

1495050613

3767058819

1186858529

5654959445

2865826858

9591192519

1002150621

9911998419

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