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:

1829785405
5423788707
1160574708
2169078872
1869105618
1163111696
1369001001
2769779729
5120250220
9810555890
6991452255
7495671451
6356354355
9123141465
8966450428
5582152821
4181881435
6464444268
0588850888
5691551359
9489394498
4074904444
3410110433
6553753765
3032530903
3532780584
9434214837
6583932957
3553511786
3072716434
5505805558
6649886466
4790777472
2659009969
0464994446
2559948259
5655803681
5050038395
0649974326
2559805318
7489673914
7408759080
3572559097
1661379900
9846493355
4156155314
9999099097
9696089065
5500555250
8333973984
9939963999
9199106921
1299911269
1091719270
1119331132
2411016239
2863068222
4993731279
8156136990
6380839172
9537389553
5080558203
0593920953
1656156816
1113131653
7235831816
7550256926
3511089653
7888780916
7262359653
8607614334
9607701501
8902926029
3323191054
9306162378
3900993909
8822778822
8847224784
6624646242
9366136561
8833833888
7222227532
7977677261
0029999520
3107371301
4387897231
5052439861
8580897282
0020787381
6631397828
9619446021
0791306190
9768632447
1001632809
2301367074
0098998999
5601366351
9369592699
2778682872
9214442124
3015932099
0735431098
4896815098
1373115021
4954416028
0021911029
6433935494
2884002948
0300006083
5446675654
3252802163
0806828034
3157771119
4507963217
9873945516
9297797772
4106400414
0174441474
3853933338
4312812449
1216596848
9259556319
9752059564
1775996398
0296564195
7554575255
9725277227
0812901819
1296366332
9419094949
0419342978
7152913290
8768696233
4752491896
8758184612
0912332933
4459141451
7893683959
4968499448
8756969955

The puzzle

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

0834441079
6774385547
1687245186
7477450852
0837324122
6833116116
7689396693
0777274727
1274441174
1797371773
4885253917
4485198743
8425776242
7575400693
3580147438
4525994451
8473434437
6483484466
7100101177
3875273327
6992142250
2432711257
6930146143
9737151398
2088787729
6030996650
2462224664
9182728779
9918111119
6697366376
0472707024
7224744470
0925454594
9493229332
4002552400
0902568887
7094537923
7005227437
9474551411
4044292045
1810686011
9819901892
3778784537
1447448974
1331331183
2039038837
8658741593
6995881597
8319589981
1852281813
0567564819
0550544563
9877751064
0840594459
0500300784
4400770707
9370404709
0550700050
8507581507
5862353655
7329629236
5828728252
7367262673
6713771173
7441175411
7311726133
7723769286
7313215648
5365155208
7317638314
8788478844
1333533113
9469499249
5886255558
9046394603
1488587037
9339484145
9786475493
9068555570
9246400089
0155855058
2967779692
0164504047
9818188888
6735753757
6835728679
0934713833
2764797594
2114159101
0267176333
0386554166
4180720169
5149670163
7732920181
8166270685
2512152199
6311621666
5518770185
6650550265
2222124521
7815341538
8084985904
0860550568
2420409244
2172112379
2736451508
5571742948
0089225238
9231380979
8615011369
5566545665
0022206242
6676797766
9599797995
1046197104
9096296765
5889596604
7442306946
8045207945
2238637765
5514467495
9233993239
7507575805
1111030115
3555531503
2726237239
9805535513
0228965509
3705633709
2710335813
4405323326
1402422384
0065320548
9746596304
6268451346
6955996580
3423372340
6151851786
4244423848
4820420304

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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