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:

2509267846
4890612636
2061410847
7372532844
5867892949
9999990994
4726412647
0461661046
6669606862
7739437749
6110416031
9818444659
3409876236
2836017039
7485074631
1665116651
7478184713
3793377339
6963014036
8922545928
7023271074
8271960201
6683451091
4294959139
0328658194
3171110171
7477878734
6699069091
1105011509
6080558076
4091524480
1497763916
1021119379
1902287557
1801529011
1407110114
5672556555
8679776776
4897288389
8021510255
4151866681
8146212566
7176261243
8176094323
0517307401
4171333311
9547005005
0555885550
8156283851
6116166611
6677577755
2805805885
0423333450
4134881414
6855758565
0105329508
6803852418
9657849239
6874883785
2837755728
2028626440
9299747299
9998949586
5455494455
0474777604
1941477695
1480045555
8743074445
3825677484
8014899696
3906695576
8921711501
7420969871
2708395539
1371833503
9999139531
3123393511
0615115006
0618161803
2572732577
6669429498
5313705148
0456529449
8730530890
2493437445
9555535495
4434353144
7797900729
8270827888
9889829849
4641949444
4216062122
1682662586
2181021081
5826757565
4286706106
4686848264
2886999781
4611609091
2121653018
8108179042
5969985946
1041745632
5926352936
6914255046
3239772932
6669665946
2727670628
8985989956
6525757028
6027241904
6839562837
7884602862
6291242460
8250651827
3355553582
1197941967
7447467424
2819441832
2220002220
8526356329
3478497289
8148436167
3144527737
8676526712
8281318318
3426534462
2094220190
1648441448
8178474448
0771971097
4269942946
8272686862
7360909469
2680558080
7270583206
2771584361
8779943381
4282901362
0367669908

The puzzle

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

5582525525
3193449513
3309039280
3632602631
4502554720
0511659585
2606452423
9240535725
5717509223
7016634630
5563351682
5618023327
4856311992
5468620295
1814585493
7618517718
0356353525
4854344555
1463466434
5524662555
0708820728
8008098084
8384382823
4483384314
3999930999
2181430793
2536128023
0643080013
9824692398
3689424309
1265256125
5155030541
4447774174
1140416402
5633936389
0584830509
9607936142
9990736472
5535116169
9387636422
8144989018
2458099991
2198223549
2158305832
8348187561
8138331313
4446886444
2394293222
2114042149
3358131335
8566605786
2240025240
9888948892
9323983399
7232574253
3800273293
1807274890
7810283290
2447804583
8513175342
5178757775
3433443334
4050303034
3129626349
9653336933
3128341108
7058376255
4673612145
4153319497
3053394081
0696250259
4223505290
8968453466
1493655297
2008457678
2268555268
5166313696
4000400450
7527757277
6998090668
0600640106
0666306630
8844888342
1091101801
8677979686
6204670386
1361776802
5559509601
0434651106
0795108146
6160779504
0954348501
0313111501
1471469204
9617271107
7313371293
0054048504
9139413497
0016171801
9091019101
3671244170
7930530636
9535774360
3573875866
0728635826
8896535698
8797994178
6663676662
4432445326
0980830890
2201325494
8294001544
4112622548
8969945204
2370871205
8722778244
6724202274
0009809408
1515581525
3292325397
3805707803
3422882483
7770407773
3099290333
8379793798
8000749479
3072203766
3420202288
3999483340
3402819359
9660896696
7961377619
5789057993
9334844839
7303737730
9333703412
1660309184
7363802794
5389095965
9961877303

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

Post a comment

Note: HTML is not permitted, URLs will be linked automatically. Spam comments will result in a permanent ban.
Type these 4 symbols into the edit field