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:

0400922894
8216648841
4556633702
7400932962
2362452905
7097710597
4848848842
2257022705
3976933969
4122452941
4146418064
2996326939
2124421824
4474567345
4196994891
7895014845
6984826954
9105866831
1335621324
8271221891
3508897288
3845817258
4645826201
3539817186
3835763277
3445777443
5871875855
3632836363
5187475157
4509749752
6048806008
3389558998
7390690699
4452124354
3554555553
4398182650
3398530889
7498884321
2058594519
4458531430
9240002402
3749947799
4289949298
8253782357
1192191920
3180164430
8299782105
3747991351
1792716061
4143190373
7631415297
2012821761
9534441587
3635325881
1796855563
9535535591
3263645263
2357825783
5772557287
9151711587
2179992758
3943199288
9760299270
0273233098
1012019280
2878772278
9899898098
2283283252
1383093280
7919919798
6665760775
0660767071
7933339073
3979239231
9858952889
8581859271
7708957278
3147162775
4784960231
9565030875
7022642200
7228425321
7478748067
8180492763
3128589696
5121152511
3282424248
8778787817
7028002707
7410515770
7095244270
9932244012
7454408160
9885238120
4286634820
5559754873
2432334260
1333749317
8051568150
2202404222
3636008336
0040400044
1203513725
8978779984
1122110266
9021070334
6913803164
2046319734
2699203935
1548410766
3498844838
9404000494
8303488336
1020420414
7612556122
1622582185
7400455751
8398429105
8404863112
1603263157
2067496877
7240234712
7375631283
4036030574
8346076773
6363736777
8888871887
7939395273
1194434114
0260602562
0688562655
0113846490
2641177929
2349508339
6184946146
2189511558
4343444444
6154242220
6641864144
0618901688

The puzzle

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

0029772729
8505000508
7804048807
8263121278
3570570573
7260740654
7065033929
8239068905
7273544790
0825123330
4242666156
3137930868
6332085398
5877233382
9245259462
8888150182
4444883464
6599569456
8376370328
8890336890
0189473992
2934580822
1281881302
7647364902
4045270439
3370373307
3035060937
2700004729
8478587452
1228171822
9667066766
7803608866
4376133633
8122787181
7464996663
9364905602
4344723945
9367608145
7306653974
7863755570
6408568711
3401024054
6441544810
3406317994
3486961722
6891313931
7404947400
6408505346
0608500600
3386060006
0019792127
4189731373
1317099321
2761698923
5795692162
7377151367
2293998923
7252252774
7655666152
9912009121
0005324881
7046731870
0145574690
7456405086
7066567128
3325353333
7556575555
0065400405
7106518010
0045704000
2392974890
2330355752
1320775401
2362728183
3862786184
8890798980
3020332323
3332823833
2662622266
1409010405
9296233463
6810283407
6513185615
6416151586
6276102309
5578175758
6816216226
6430164300
9601119117
9253252929
4092933066
1174625299
3552635966
7198897925
3801693967
1266113266
9562595260
2612121927
7717717077
2992935299
0051849716
0599345716
8594122271
5139646771
2844635816
4334334371
2262222216
1114747713
6146146216
2684325834
2179325575
0527521837
0921341723
0924538583
6527164669
6975199575
0579353799
6568556856
0521813552
2127972992
2290164557
9700663621
3105560550
0875860952
8694254550
5555555953
5090500560
2223362132
4764664657
5257723571
9509905399
6688482164
4601031604
6191155491
7713557321
5425651121
4229630391
7625482324
7962532301
9092281364

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