2012-11-17: Puzzle - First to solve wins

Posted at 2012-11-17 02:35:21 by SHD

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:

1474976411
5928899255
8631488846
1908909099
0138731703
1408742098
8938461087
1634882892
0438951763
0934150493
9603976861
9528287797
9818763180
4535674740
4620708991
4633777634
1514141421
7668977998
9822669222
9200220002
2693355581
3365385448
0863657592
5160504491
0130521475
5030553305
3600560396
2861326888
0355330330
8163636383
7844477448
0910119097
0888888608
1477636847
5591951749
3165057447
5588081437
5413857049
3423719748
8308079848
8340234235
6092120962
4845545455
6123737171
5066996656
4863580636
8090785667
5129738981
5045723993
5322978254
0567357035
4093110404
6315151131
8061910069
4265555756
0067502622
4361992683
8567519607
8387398362
4095150353
1850506150
6172002606
0880440008
9848898848
9019790099
1810729475
9870087249
9888729725
1640080957
9010599733
0083544341
3265993461
8862997497
7375656540
3862566194
3063116001
3857585572
0383703730
8835989983
7282688227
2210820573
1897721971
3114091943
9200210570
8508836571
1901331901
1176486174
9920991042
9028020509
3378718373
9641214191
9881618611
2261222222
9525352505
3096119610
2621122143
3535132425
3891282807
2581285267
2645398414
6204776440
7097500959
3854633154
4698778879
5468156454
3494583715
3850182123
4858763867
7604621789
6894138408
2163431642
4662866428
7735075507
1181013180
1121111621
3519233400
3091311681
4100961180
5374210500
2537635641
9358614512
0837725618
3209827618
4117838631
6425017719
1011991605
2213134112
1117717788
0031118031
2390225609
7082986277
0852305050
6028128108
6693563955
8791379717
0851989398
0682548005
6022518200
6024119907
6051350051

The puzzle

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

8443510389
5737320273
4304010189
1227755289
6918810083
5582510275
5806656083
9539355379
8662826283
1444330419
2251987521
4379027046
6131049521
7413443825
6517098329
3227997321
8418548415
2929929526
4899113849
9000210025
4281412144
2625656352
4067470747
3489443998
2917777227
2469783821
4669677571
4625728769
3581486979
2989429706
2299009992
4775545247
3493093034
7869876928
6772773368
3812079397
9688345248
8554803367
6695443939
7926173298
9515628720
6764677320
1569672319
6759060218
9764785417
6259799655
9755675957
5864884865
9214841819
1527661519
8182185389
8484684355
7419976807
3695984254
8971076287
5447775405
4288784357
7207070214
3733773487
2622876289
6602442760
8581518015
9216661194
1211211247
0505750079
2195212279
6541145040
7881561270
6187412214
9586858247
2674363539
8839317306
6753444210
6824444552
9628304571
8689339968
9724544929
5053450504
2824112278
6078585606
3082930889
8733133388
4848384844
2984332241
8589355838
8082988552
4589359710
8683344463
2583109932
4032380138
1689180106
9178146140
3182028944
9675031264
9000185971
9190779977
1684448261
7372132122
3049430444
9605050906
3314314341
0630040268
8007887908
8220285220
3349333649
7347014668
6540917921
1746240261
5543984208
1909137760
6718864490
4437684191
7607188131
0011584291
6958814338
7707777380
1613116031
2823128431
4481384238
9001084190
7419717777
2368466622
5530805545
7863232667
5923772357
7469725643
2960885676
7563867200
2569904805
5823844347
9231110293
5555585507
2720808237
3008370131
3775553176
5867813107
9470650237
7584407297
3819053571
9938388137

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.

Tags:

Comments

Big Ben

Posted at 2012-11-19 09:55:28 by Colin Edward

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.

Posted at 2012-11-19 13:48:31 by Steven Don

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.

Posted at 2012-11-19 16:36:10 by Batuhan Bozkurt

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.

Posted at 2012-11-19 17:10:02 by Steven Don

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