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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:

1577571652

2383849388

2272881722

3723732273

4062071723

8193282358

3570749722

7051471758

0699881370

0790200770

1297597713

2685050255

6700777607

0697569093

1087003074

0795252265

5795061647

0200742560

8780680151

0640613154

2024969154

5446893659

1212194612

6615610656

4929249321

9905190159

8366963964

5380755400

7150453364

8303921806

3707835100

5953151399

0606003660

8660930196

5515155106

7322427834

1681288162

5806886808

1110707171

2333393243

1407092141

3542988142

8455482143

1573943234

5948482871

0934272583

3994071272

1373070261

2776495202

0070770503

1221211222

7815895781

2999272279

4366146185

3662362332

7782882287

8336688639

1465754464

1685787933

7762711661

0686373960

1496863520

7662843172

0816059355

7895581555

7814394321

2733856451

6255551552

4824285324

4444446451

9499984295

1616696361

0685008858

3117917973

3222363232

3555535537

2777810558

9906330538

2534038838

4020023638

2537618298

3508770558

7581665676

9210001122

8631933033

8588741231

9693984415

0538358668

0561672253

7281062777

5946111994

3424924347

6128525515

4300550330

4950584543

6424531865

6922522321

3306998498

3740946844

8896446886

5379872993

7732537357

4074337744

7374541788

7772496480

8032107312

4396486234

9536813066

1811181389

5045005504

0606101016

3060399073

0879235314

1610701364

0278701010

6596291074

9936238116

6364101985

3784302123

3424564691

6885144888

3385333833

3704600753

3664563545

6824114646

9185318338

## The puzzle

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

0431640346

0914694624

9516755971

5637113173

9411741955

0512082164

9916658900

5616134088

0418060302

7773735797

0220202230

2453440932

2544954289

1859070592

1325040699

1694334987

7711805780

9332401299

6551115555

6892396662

9239424949

2074331223

6852365132

6894449024

4274369815

1571358597

6074315096

7375905577

5079056770

5472715900

7241010573

7775117526

3688686547

0000501500

7717715777

5007050273

2005707075

0681210716

7610377306

1302991011

1600782970

7681944159

9050934866

0402255104

1000710051

8323682232

2114711221

9715111111

0808118150

9315105855

6924770144

8913144111

0328612398

1322689248

2974129462

4058152235

7120189330

5910104867

2929192990

5030105130

7254852444

5177677771

4615555415

8761939171

4204193004

4206645374

7161903861

7278177773

4161614466

8764987967

1306838161

3101903311

1917711379

0447666467

9892990982

5255979552

5718276172

0552999168

2271816968

3511546957

4783021167

3805082100

3859388427

0809022544

5859123091

0409110000

2179297872

6700370303

3849099384

5859665868

4054005400

5102515200

0880101487

3362979236

6473615287

4799175289

4251215280

8376379386

5150511488

0083605003

7065606557

3820022200

7800557005

3860567268

3020510162

0925669165

3008338451

7980292189

3852252386

1000101105

7744790474

1811353112

9183631176

2843953112

2239793374

6883953372

6009101512

9598088445

1505185818

0094181605

5772815647

5468338645

5857885857

6197681469

1343333418

4155414745

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