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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:

9515322291

5202725231

1005782391

4832272738

5537775398

4224222234

8486868730

1210660221

7713171351

7015115777

9416550596

9424342444

4682332633

7614366761

9475122777

9429307364

4112495733

9025224591

2927287922

9080309320

0258250082

0191991010

0318650022

8060357022

2824601922

0229489022

1089870320

8740567805

4425134809

6395592938

9694694594

0930737109

9056669105

9980894598

0444447804

2082872908

2263784431

4113734935

4110723583

5040769307

4419774944

4060704074

6743886338

7213737332

5170600054

5419768309

6520496108

2210474072

6519121083

2220112202

6515151615

5429592444

5541811215

7797449777

9611429141

6201498594

5825399197

9007499794

6996990696

5254225241

9490019740

4989090694

4144848147

0005092263

1208143675

4203099225

8732659507

4646995463

1619191527

9996949673

9322903295

6690454609

6786567585

5228057220

8580558855

6062772060

6282502752

8708728578

6269780842

6768652186

0288767290

2814145414

4798775466

2808267114

7810675176

8646919466

1999495415

7551475414

7771617276

5415145156

2221212221

9349143791

7890009273

1001550115

4788239741

0162543053

2203652273

8689030221

4230000271

2877559884

6402192222

2076111278

2477163804

6879595755

2872118228

2816566855

9408585058

6037166314

0401504904

4383708953

5130100308

4887614852

1101710107

8844854883

9575606955

0009904094

1113318352

2487582575

1994441414

7474977954

5945111994

7944124686

1964485494

8077163901

5994440982

5947442979

## The puzzle

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

5878350002

4000914184

8756164844

0255810924

2845952894

2022910924

0125260256

6494462149

0044114002

6072666672

6604336090

4919299994

1205313310

6942342226

1216378642

6604257160

4945247482

7075957222

8515175201

9273685391

8332795250

6210215507

6256115256

2922092320

0606166301

8576701567

9177170791

9575690862

0725023642

1953056391

0402650634

3250550932

9898884869

9036903691

4440340344

1628126471

4358753880

2270422024

7561471756

2751352227

2358783025

8240781716

2341360266

2388409438

7368441620

2827876145

6898384949

6897035909

6573726036

2175377332

6593069345

3138888838

6445745754

7897698787

6571901447

9454990569

7754588343

9774168840

9794594879

6252922925

7791471777

3573003373

9070100100

6794775126

3172760772

7796230810

7493786940

2523758257

6396939966

8714718774

7492272494

3156757316

6405888510

3257923755

0734673346

8910518955

1704905047

8417803687

1230633138

8400645693

0759537238

9986943547

6775346531

0256163547

8456012197

3111153171

8897862938

2484442846

3576362537

7771116897

1681190691

3250335220

1191441791

6662776862

7516031680

4762045760

6521975681

7544070281

3506101881

6668653686

9454495448

8886447689

1365151069

0837251689

8142258469

8818593088

9342058696

9882045169

6471641864

3216332663

2537995932

0175310103

3176347045

5519669036

6571311799

2437619872

0516061790

3831741554

8326210242

7024400058

8245011242

5754753047

4514515545

0104101054

8222261282

0296940292

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