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Guest Message by DevFuse

Five encrypted thoughts

18 replies to this topic

#1 superprismatic

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Posted 30 July 2011 - 05:44 PM

This 324-character message is an encrypted quotation:
```XPRXWUIWUOLZYXBFTTJMDVOCTTXPPPKLEVROQPRFPLTHWSMOGVCYPG
LHKHKLSJSLGKZYFYBUTFTOSFHHMZGRQFELYEKFHWILBDBDROHIZLIM
MILZIHORDBDBLIWHFKEYLEFQRGZMHHFSOTFTUBYFYZKGLSJSLKHKHL
LHNZTBTPXFWOIHZVAOXVNJRMYUBGMOAAOMUYXHMARGFWPYGEIHJISQ
GPYCVGOMSWHTLPFRPQORVELKPPPXTTCOVDMJTTFBXYZLOUWIUWXRPX```
which was encrypted in the following simple way:
1. The quotation has been converted to numbers using A=0, B=1, C=2, ..., Z=25.
2. A second stream of numbers is made by reversing the sequence of numbers made in 1 above.
3. These two streams are added modulo 26.
4. The stream produced in 3 above is then converted using 0=A, 1=B, 2=C, ..., 25=Z.
The result of all this is the 324-long stream above.

Here is an example of encrypting a different quotation:
`ITHASYETTOBEPROVENTHATINTELLIGENCEHASANYSURVIVALVALUE`
```I  T  H  A  S  Y  E  T  T  O  B  E  P  R  O  V  E  N  T  H  A  T  I  N  T  E  L  L  I  G  E  N  C  E  H  A  S  A  N  Y  S  U  R  V  I  V  A  L  V  A  L  U  E
8 19  7  0 18 24  4 19 19 14  1  4 15 17 14 21  4 13 19  7  0 19  8 13 19  4 11 11  8  6  4 13  2  4  7  0 18  0 13 24 18 20 17 21  8 21  0 11 21  0 11 20  4
4 20 11  0 21 11  0 21  8 21 17 20 18 24 13  0 18  0  7  4  2 13  4  6  8 11 11  4 19 13  8 19  0  7 19 13  4 21 14 17 15  4  1 14 19 19  4 24 18  0  7 19  8
12 13 18  0 13  9  4 14  1  9 18 24  7 15  1 21 22 13  0 11  2  6 12 19  1 15 22 15  1 19 12  6  2 11  0 13 22 21  1 15  7 24 18  9  1 14  4  9 13  0 18 13 12
M  N  S  A  N  J  E  O  B  J  S  Y  H  P  B  V  W  N  A  L  C  G  M  T  B  P  W  P  B  T  M  G  C  L  A  N  W  V  B  P  H  Y  S  J  B  O  E  J  N  A  S  N  M```
The result of this is the 53-long stream:
MNSANJEOBJSYHPBVWNALCGMTBPWPBTMGCLANWVBPHYSJBOEJNASNM

What is the quotation which has been encrypted to the stream above starting XPRXWUIWUOLZYXBFTTJMDVOCTTX... ?
• 0

#2 Nana7

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Posted 30 July 2011 - 06:31 PM

Very interesting! This is going to be loads of fun, woohoo.
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#3 Nana7

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Posted 31 July 2011 - 01:55 AM

This one is hard. I do not suppose we can get a hint like what letter 162 should be?
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#4 superprismatic

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Posted 31 July 2011 - 02:54 AM

Spoiler for Letter 162 is

I have hints in the form of words which appear in the text. I'll post them (one at a time, of course) if you want them.

Edited by superprismatic, 31 July 2011 - 02:56 AM.

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#5 Nana7

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Posted 31 July 2011 - 03:03 AM

I am starting in the middle and working out, so words would not help me any, unless I knew where they went maybe. That letter is helpful, I had skipped past it.
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#6 superprismatic

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Posted 31 July 2011 - 03:08 AM

Good. If you need any small hints, I'm willing to dribble some out now and then. Just ask.
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#7 Nana7

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Posted 31 July 2011 - 05:03 AM

Okay, letter by letter is getting me nowhere fast. I think that a brute force with a dictionary could probably break this pretty quickly though, but I do not have access to that other than manually, which would be pretty slow. I can find a word if it is in there somewhere, so I will ask for a word hint please.
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#8 voider

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Posted 31 July 2011 - 11:15 AM

Interesting, but I am sceptical about whether word hints will help solve subsequent parts of the message unless there are a lot of words given. I'm going for bruteforce.
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#9 thoughtfulfellow

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Posted 31 July 2011 - 01:38 PM

Spoiler for My thoughts

Edited by thoughtfulfellow, 31 July 2011 - 01:39 PM.

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#10 superprismatic

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Posted 31 July 2011 - 03:24 PM

Okay, letter by letter is getting me nowhere fast. I think that a brute force with a dictionary could probably break this pretty quickly though, but I do not have access to that other than manually, which would be pretty slow. I can find a word if it is in there somewhere, so I will ask for a word hint please.

Spoiler for word hint

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