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:

4939927468
9599227868
9383883873
0531053872
5932833873
6663331966
4333343073
0777723778
3733337808
8228682462
9636667894
6996779896
5577887735
2040420413
7718137718
5882037738
9020627713
6855070818
4943673795
2518829718
6945667965
3331888331
1676861777
3608606363
8020558202
3931546897
6650678709
8306697101
3675677379
3306676207
5326562044
5320630420
9361531473
9626605565
9320588220
4326554242
5356565565
9221619626
9318610833
1560006010
1304660466
8866881668
2215212252
0988500959
6976559669
8985561196
1878911319
1964576890
1818551869
1964267386
5643943434
5742490319
0722926750
5722613355
5423504648
5772557475
0149441444
7683868883
9728929272
5482945952
0422242207
5152547581
6649968949
8898808689
7714715774
5718212984
5313648501
6722665589
8360985241
6371618787
0659219556
1685320482
9756612030
9689578721
6755364633
1189318913
9724929722
9855298587
6935663663
0679579907
0152949229
0772718711
1904023925
2207429231
4186253605
5177713735
2650652706
0996229629
9918108911
7322373225
9010130844
3147943946
9090119677
0110914622
3117187069
9140911904
6517777717
7005077747
3110633130
9692191991
9372378388
9576321411
2904506783
4604532159
2876547117
4614515641
2976529725
3302020302
9086566990
9804387333
7253637655
1542921219
4402500142
7150371350
7377977797
4457548258
4153470733
1270583693
7202676485
7252989669
1037082298
9897722319
3738302319
3303962818
3379277111
7239377319
8008002808
8251185211
7799791799
8218122188
9731830883
9487107491
9968591525
3756283016
9939567843
9951195111
5288258215
9776876779
3639553333
9367569993

The puzzle

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

3479590903
0409214805
1113117502
3082880305
6012494905
9822990823
7278783707
3333494232
6911916945
0107017503
4202777820
9072392399
4670606607
3475275343
2490994009
3470923175
4272783579
2440972288
3272743150
9672616242
2835698486
3319593943
3594007493
9022192647
5864253199
2969992169
1848554387
6994497496
9309908923
3434383743
4386333486
4220024200
9111129117
9944299242
2995535931
1072033187
1474995906
4285125982
5613338942
6866529247
9301649549
2338015219
1093345581
5801809247
0206614448
7271313273
4542442541
4483409478
1484814589
4665645667
2420400427
4687664782
0775074700
8863667839
0550550008
9522477037
3046307709
8009964002
8709364882
6304937487
3175527855
3897564188
6014896503
1050500672
1891509374
7910170011
3177517737
3791917313
1014811801
6852868554
3245558660
7965223920
3955164550
0629512869
7546181843
7227572228
3669163636
9982222922
0246944420
8535253553
2922291932
2117217922
8084008839
7566769547
6265336542
1862897922
1058861942
0978306532
5183477949
7604199537
1001008110
6858468354
6474447464
6776757476
6241134961
6560638370
4373964460
3116017161
5978908966
9256338174
2873678866
9220820994
1232122321
1592444411
6360555666
2533160405
9836465030
6232416057
1370550502
1562571984
0296229609
1005704105
8862282622
8777077777
1381331131
8086383755
1002030999
0775213700
3877368414
1372258082
4516859322
4160654472
7731359034
3976937424
7714039322
1135319310
3444339434
7531351437
0004117024
2270774502
5140830872
9247859554
0149620421
9140612069
9340107696
5170951570
3142913691
6743667434
9347838998
6229169622

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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