## Puzzles from the xkcd book (big puzzle SOLVED!)

A forum for good logic/math puzzles.

Moderators: jestingrabbit, Moderators General, Prelates

### Puzzles from the xkcd book (big puzzle SOLVED!)

Is anyone making progress?

So far I've only done a few easy ones.

Page 10101:
Spoiler:
Simple substitution cipher, but with stick figures, a la The Adventure of the Dancing Men. The plaintext is "started with four letters but only need three what a riddle what a mystery." I'm not certain what it means.

Page 11001:
Spoiler:
Assuming z is at least 2,
\int_0^\infty t^{z-1} e^{-t} dt=\left [-t^{z-1}e^{-t} \right ]_0^\infty+\int_0^\infty t^{z-2} e^{-t} dt=\int_0^\infty t^{z-2} e^{-t} dt.

So by induction, this is equal to \int_0^\infty e^{-t} dt=[-e^{-t}]_0^\infty=1 for any whole number z. I'm not quite sure what 1ing is, so I may have made a dumb mistake...

Page 110120:
Spoiler:
The start of the tenth-favorite word used by Bender: C (for Chump)
The toon that went south while commanded by Ender: B (first battle, against Rabbit)
The number of lights that Picard said were on: 4 (Chain of Command)
And the class of the planet where Kirk shouted "Khaaan!":
I'm not sure about this one - it's been a while since I watched Wrath of Khan. A friend of mine, who's a bigger trak geek than I am, says this took place on Ceti Alpha V, which Memory Alpha lists as "barely class M" prior to the events of WoK, but was class H during WoK. However, the WoK article seems to imply that the enraged shout took place not on the planet but on an asteroid. My guess is H, but confirmation would be nice
The rings of the men minus rings for the elves: 9-3=6
And the product mod ten of a foursome of twelves: 124=24=16=6 (mod 10)
The end of a code NES gamers know: assuming you don't count select+start, A
And the base used to model how quickly things grow: e

When xor'd together, we're supposed to get 'E', but this doesn't seem to be the case (unless the planet was T class, which seems unlikely), so there must be some mistake here.

Also, I'm not quite sure what's up with the page numbers. As far as I can tell
Spoiler:
They are all sequences of 0s, 1s, and 2s, in length-lexicographic order (which is the same as increasing order of the number they represent in base 3, or any base >3 such as 10) such that a '2' can only be followed by '0's. I can't come up with a nicer description, or any reason why this would be interesting.
Last edited by skeptical scientist on Tue Mar 09, 2010 2:26 am UTC, edited 1 time in total.
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

For the page numbers
Spoiler:
perhaps it is supposed to be in base 3, but the omitted numbers represent some sort of code?

And for the last page of the introduction:

Spoiler:
As far as I know, this is also a simple substitution: okay here we go
lu6cifer wrote:"Derive" in place of "differentiate" is even worse.

doogly wrote:I'm partial to "throw some d's on that bitch."

lu6cifer

Posts: 230
Joined: Fri Mar 20, 2009 4:03 am UTC
Location: That state with the all-important stone

### Re: Puzzles from the xkcd book

Also, Redditors solved the puzzle labeled To: Reddit (page 11011) here. (Spoilers ofc.)
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

skeptical scientist wrote:Page 110120:
Spoiler:
The start of the tenth-favorite word used by Bender: C (for Chump)
The toon that went south while commanded by Ender: B (first battle, against Rabbit)
The number of lights that Picard said were on: 4 (Chain of Command)
And the class of the planet where Kirk shouted "Khaaan!":
I'm not sure about this one - it's been a while since I watched Wrath of Khan. A friend of mine, who's a bigger trak geek than I am, says this took place on Ceti Alpha V, which Memory Alpha lists as "barely class M" prior to the events of WoK, but was class H during WoK. However, the WoK article seems to imply that the enraged shout took place not on the planet but on an asteroid. My guess is H, but confirmation would be nice
The rings of the men minus rings for the elves: 9-3=6
And the product mod ten of a foursome of twelves: 124=24=16=6 (mod 10)
The end of a code NES gamers know: assuming you don't count select+start, A
And the base used to model how quickly things grow: e

When xor'd together, we're supposed to get 'E', but this doesn't seem to be the case (unless the planet was T class, which seems unlikely), so there must be some mistake here.

As far as page 110120:
Spoiler:
And the class of the planet where Kirk shouted "Khaaan!" < I _think_ this actually happened on whatever planet the research station was on-- Memory Alpha says this was Regula and it's class D *shrug*
And the product mod ten of a foursome of twelves < My book says "fivesome", not foursome, which would make this 2. I think.

Page 1012:
Spoiler:
's just braille. Says "It takes more time than you expect but less than you fear", if my ability to look up the braille alphabet on wikipedia hasn't failed me.
FallenNicolae

Posts: 4
Joined: Tue Sep 22, 2009 9:16 pm UTC

### Re: Puzzles from the xkcd book

FallenNicolae wrote:As far as page 110120:
Spoiler:
And the class of the planet where Kirk shouted "Khaaan!" < I _think_ this actually happened on whatever planet the research station was on-- Memory Alpha says this was Regula and it's class D *shrug*
And the product mod ten of a foursome of twelves < My book says "fivesome", not foursome, which would make this 2. I think.

Thanks for pointing out the foursome vs. fivesome mistake. I'm still not sure about the planet, though, since xoring still doesn't seem to give E.
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

Page 11002:
Spoiler:
This one uses Aleut numbers, apparently: the top, for example:

uataqanuung qsichingnkuchaang chsichingsichingng sichinguluunguung chaangataqanchataqanng

u-ataqan-uung q-siching-nku-chaang ch-siching-siching-ng siching-uluung-uung chaang-ataqan-ch-ataqan-ng

ataqan is the aleut number 1, for example; siching is 4, uluung is 7 and chaang is 5. Subsituting these gives:
u-1-uung q-4-nku-5 ch-4-4-ng 4-7-uung 5-1-ch-1-ng

Assuming 1337 speak, and cross-referencing with the list of Aleut numerals gives:

uluung qankus chaang atuung siching

giving:

7 3 5 6 4

the bottom:

siching-ul-uung-uung h-siching-ul-uung-ataqan-m'-'siching-ul-uung-siching-q-siching-n nu-ataqan
4-7-uung h-4-7-1-m - 4-7-4-q-4-n nu-1
6 hatim-ataqan nul

I can't find any reference to what nul could be. possibly zero?
6 11 "nul"

(http://www.unilang.org/wiki/index.php/Translations:_Numbers_-_Unangam_tunuu <source)

EDIT:
skeptical scientist wrote:
FallenNicolae wrote:As far as page 110120:
Spoiler:
And the class of the planet where Kirk shouted "Khaaan!" < I _think_ this actually happened on whatever planet the research station was on-- Memory Alpha says this was Regula and it's class D *shrug*
And the product mod ten of a foursome of twelves < My book says "fivesome", not foursome, which would make this 2. I think.

Thanks for pointing out the foursome vs. fivesome mistake. I'm still not sure about the planet, though, since xoring still doesn't seem to give E.

Spoiler:
CB4D62AE = 1100 1011 0100 1101 0110 0010 1010 1110

1100
1011
0100
1101
0110
0010
1010
1110
------
1110 = E (Assuming I'm remember correctly that xoring multiple numbers together gives you 1s if there's an odd number of 1s in a given place)
FallenNicolae

Posts: 4
Joined: Tue Sep 22, 2009 9:16 pm UTC

### Re: Puzzles from the xkcd book

Oh, I'm dumb. I was thinking ascii instead of hexadecimal.
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

Something else odd I've noticed:
Spoiler:
Several of the comics have had text changed.

The comic on page 1101 has different pointers than the one online.

The comic on page 10020 has different text on the last panel (I think, I can't remember what the original strip is called-- having the titles of these would be nice) but I think it used to end "It turns out wanting something badly doesn't make it true" or something.

The comic on page 10100 has the time as 2:07 and the factorization as 3x3x23 instead of 2:53 and 11x23 in the one on the web. Wonder if this has something to do with the random block of squares on the page referenced in the comment on it?

EDIT:

and the alt text for the very first one isn't right- On the website it's something about how it was the first drawing he did for the website, in the book it references e and the square root of 2... could be hints. or could be the original alt-text and it's been changed in the years since. *shrug*
FallenNicolae

Posts: 4
Joined: Tue Sep 22, 2009 9:16 pm UTC

### Re: Puzzles from the xkcd book

This is an easy one. On page 1:

Spoiler:
CNEG BAR BS RVTUG VA URK: RR AVAR RVTUG SVIR BAR BAR RVTUG is just ROT13. It says, PART ONE OF EIGHT IN HEX: EE NINE EIGHT FIVE ONE ONE EIGHT.

So I'm expecting 8 hex codes which will form up into... Voltron? Or something equally cool.
dkurth

Posts: 1
Joined: Thu Sep 24, 2009 8:45 pm UTC

### Re: Puzzles from the xkcd book

Page 100012:

Spoiler:
The symbols are QR codes. I was able to take a picture and decode the top 3 and the bottom, but the 4th wouldn't. I'll take another later and try, but the others are:

1: Toad's Factory 2:00.776
2: Coconut Mall 2:08.147
3: DK Summit 2:03.351
4:
5: Thanks, David and Ashley.

Which I believe are Mario Kart levels (and presumably times)-- makes sense given the comic on that page.

And another oddity related to my previous post and probably the one on page one:
Spoiler:
Page 1111, says "3 of 8": The binary in the comic is again different than the one that's online.
FallenNicolae

Posts: 4
Joined: Tue Sep 22, 2009 9:16 pm UTC

### Re: Puzzles from the xkcd book

dkurth wrote:This is an easy one. On page 1:

Spoiler:
CNEG BAR BS RVTUG VA URK: RR AVAR RVTUG SVIR BAR BAR RVTUG is just ROT13. It says, PART ONE OF EIGHT IN HEX: EE NINE EIGHT FIVE ONE ONE EIGHT.

So I'm expecting 8 hex codes which will form up into... Voltron? Or something equally cool.

Spoiler:
Damn it, I looked at that and assumed it wasn't a simple substitution cipher as there was a word consisting of a single doubled letter!
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

skeptical scientist wrote:Is anyone making progress?
Page 11001:
Spoiler:
Assuming z is at least 2,
\int_0^\infty t^{z-1} e^{-t} dt=\left [-t^{z-1}e^{-t} \right ]_0^\infty+\int_0^\infty t^{z-2} e^{-t} dt=\int_0^\infty t^{z-2} e^{-t} dt.

So by induction, this is equal to \int_0^\infty e^{-t} dt=[-e^{-t}]_0^\infty=1 for any whole number z. I'm not quite sure what 1ing is, so I may have made a dumb mistake...

I think that's incorrect:
Spoiler:
The answer seems to be the gamma function of z, Γ(z). (Also think it's just a joke related to the comic as opposed to part of some larger puzzle.)
L33tminion

Posts: 1
Joined: Fri Sep 25, 2009 5:30 am UTC

### Re: Puzzles from the xkcd book

Right of course.
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

I guess that the first three 'parts of eight' are on pages 1, (11 or 111?) and 1111 (since 1111 is 3 of 8 )

Spoiler:
And maybe the one on page 1111 is 160153... (the two numbers of the comics concatenated) because otherwise I don't really see anything special in these two comics..

edit :
Spoiler:
oh nevermind... from a higher post, I guess the binary numbers from the cypher comic are the ones to look at, so, in hex : da 10 1c bc
Last edited by Vhailor on Mon Sep 28, 2009 2:36 pm UTC, edited 1 time in total.
Vhailor

Posts: 18
Joined: Sat Aug 04, 2007 2:32 pm UTC

### Re: Puzzles from the xkcd book

page 111, just solved it, didn't see it posted anywhere so:
Spoiler:
simple replacement encryption, decodes as:

it's impossible to measure love, and without measurement there can be no science. When it comes to love, we're all in the dark, --kinsey

oh, and page 11.. not sure I fully understand but:
Spoiler:
1 0 T A E / K E
2 0 I B S W I Y
0 D E 6 5 T N 8
C O 2 5 . R A P

it is hard to say which is 1, and which is I, and O-0, and 5-S. However, there's a message scrambled inside the block, says something like:
'a bitwise key code part'.
When removing the letters that consist the message we're left with:
10/
20
0658
25

not sure whether they're the keys for deciphering the message, or part 2/8 as suggested above.
yehudasa

Posts: 6
Joined: Mon Sep 28, 2009 7:25 am UTC

### Re: Puzzles from the xkcd book

good idea yehudasa!
page 11:
Spoiler:
I could find something that could make slightly more sense, something like:
part 2/8
256bit AES key code WIN
and with all those letters removed we are left with
10005

so maybe we need to use the key to decrypt the part? (I'm not too sure about the WIN part... maybe it's just 'in' and there's a W among the numbers at the end...)
Vhailor

Posts: 18
Joined: Sat Aug 04, 2007 2:32 pm UTC

### Re: Puzzles from the xkcd book

Spoiler:
If you walk over the letters, starting at the top left, you can get the following:
10020 code 256 bit aes w/ key in 8 parts.

10020 contains the big hexadecimal code, so it makes sense.
yehudasa

Posts: 6
Joined: Mon Sep 28, 2009 7:25 am UTC

### xkcd: Volume 0 Cyphers

Edit: Apparently my thread got merged with this one, which I didn't see when making mine. In any case, here's a list of all of the codes and such in the book and my work on them. I've marked the ones I solved with a red asterisk. skeptical scientist has already added the rest of the information from this thread below.

Note: In a couple places it's unclear whether it uses 0 (zero) or O (capital o) and also whether it uses 1 (one) or I (capital i). Where there are both alpha and numeric characters, I've used 0 and 1, pretty much arbitrarily. Please correct me if this is wrong.

*1. Page numbers
Spoiler:
The pages are numbered in "skew binary" whereby each digit represents a multiple of 2k+1-1.

So 10112skew would be 1*(25-1)+0*(24-1)+1*(23-1)+1*(22-1)+2*(21-1)=31+0+7+3+2=43.

Skew binary also has the property that all digits are either 0 or 1 except for the rightmost non-zero digit.

2. 15 11 1 25 8 5 18 5 23 5 7 15

*3. CNEG BAR BS RVTUG VA URK: RR AVAR RVTUG SVIR BAR BAR RVTUG.
Spoiler:
It uses ROT13. It translates to "PART ONE OF EIGHT IN HEX: EE NINE EIGHT FIVE ONE ONE EIGHT."

4.
Code: Select all
1 0 T A E / K E2 0 1 B S W I Y0 D E 6 S T N 8C 0 2 5 . R A P

5. CY-O CMLROOCXN. YR M.AOGP. NRK.W ABE ,CYDRGY M.AOGP.M.BY YD.P JAB X. BR OJC.BJ.V <D.B CY JRM.O YR NRK.W ,.-P. ANN CB YD. EAPTV [[TCBO.F

6. There are a bunch of dots on page 1012, possibly braille . I have no good way of typing it.

7. On page 1111 it says "3 OF 8". I'm not sure whether this is a code or not. It could very well refer to comic 153 on the page. Then again, the comic itself could also be part of the code.

8. The comic on this page is #240, incase it's connected.
Code: Select all
662A3A35 DEF88CA7  0BDFD186 20B05684  934721F8 F64762FD03F8D76B 3FA0CB8C  2756B2D0 A9F00A1B  CFF1603E DB05426C

9. 101110
Spoiler:
The comic is #247, but the one in the book is different from the one on the site. In the book, the time is 2:07 and therefore the guy says "207 is 3x3x23" and then in the last panel the time is changed to 14:07.

10. On page 10101 there are stick figures posed in various ways. Again, I have no good way of typing this.

11. 0011001001011100000101100000110111100100001010100110011000010010110011

12. UATAQANUUNG QSICHINGNKUCHAANG CHSICHINGSICHINGNG SICHINGULUUNGUUNG CHAANGATAQANCHATAQANNG

On a different place on the same page: SICHINGULUUNGUUNG HSICHING ULUUNGATAQANM- SICHINGULUUNGSICHINGQSICHINGN NUATAQAN
Note: there's a new line after the "-" so I don't know if it's part of the same word or not.

*13. To: *drawing of reddit alien*
Code: Select all
GJNHIYTOTNNNBSFOEVYYVTNAQGYIUAEIEAIAEURFYVGULGBIREOUKEGEAEEPFQVQTLEDVYSRNVNJULRNAQTVZOYRVETOHRHEWSWHAGURJNORNYYZVZFDESFYIEIOPELJRERGUROBEBRLGNVNLSDKETEBI

Spoiler:
I went searching for this one on reddit and of course they already had it worked out.

First, you use ROT13 again to produce the following:
Code: Select all
TWAUVLGBGAAAOFSBRILLIGANDTLVHNRVRNVNRHESLITHYTOVERBHXRTRNRRCSDIDGYRQILFEAIAWHYEANDGIMBLEIRGBUEURJFJUNTHEWABEALLMIMSQRFSLVRVBCRYWERETHEBOROEYTAIAYFQXRGROV

Then, you remove the parts of the code which are part of Lewis Carroll's "Jabberwocky". He actually incorrectly wrote the last word (or the part of it that's there) wrong. It should be borogoves, rather than borogroves.
TWAUVLGBGAAAOFSBRILLIG
ANDTLVHNRVRNVNRHESLI
THYTOVE
RBHXRTRNRRCSD
IDGYR
QILFEAIAWHYEANDGIMBL
EI
RGBUEURJFJUNTHEWAB
EALLMIMS
QRFSLVRVBCRYWE
RETHEBORO
EYTAIAYFQXRGROV

Code: Select all
UVLGBGAAAOFLVHNRVRNVNRRBHXRTRNRRCQILFEAIAWHYRGBUEURJFJUQRFSLVRVBCREYTAIAYFQXR

Then, you have to use ROT13 again to get this:
Code: Select all
HIYTOTNNNBSYIUAEIEAIAEEOUKEGEAEEPDVYSRNVNJULETOHRHEWSWHDESFYIEIOPERLGNVNLSDKE

Then, rearrange the rows thusly:
Code: Select all
HIYTOTNNNBSETOHRHEWSWHYIUAEIEAIAERLGNVNLSDKEEOUKEGEAEEPDVYSRNVNJULDESFYIEIOPE

And then read down the columns and you get "Hey reddit I love you guys thanks for everything nine eleven was an inside job wake up sheeple"

14. HALF OF WHAT YOU SEEK IS HERE / AND HALF YOU'VE SEEN BEFORE
SO WHY DON'T YOU WISE UP A BIT / AND DIGG A LITTLE MORE

429C6822BE41C334BE616EFFF8B5A320

15. On page 100012 there are 5 QR codes.

16. There's some pixel-y thing on page 101110 that I don't know the name for.

17. There's a random "DO" on page 110102, I don't know if it's a code or not.

18. The start of the tenth favorite word used by Bender
The toon that went south while commanded by Ender
The number of lights that Picard said were on
And the class of the planet where Kirk shouted "Khaaan!"
The rings for the men minus rings for the elves
And the product mod ten of a fivesome of twelves
The end of a code NES gamers know
And the base used to model how quickly things grow
When they're XOR'd together the checksum is "E"
Which will tell you you've got the penultimate key

Spoiler:
C, for "Chump" from "War Is the H-Word"
?
?
?
9-3=6
12^5 mod 10 = 2
?
E

19. 123 B *picture of an arrow hitting a wall and bouncing off*
VRDSYLRBYSMRLUVRXGCFHZWXKYNHYKLKWMCLRMFIKOZAIYXJWITOYOVN
Last edited by e^iπ+1=0 on Sun Oct 11, 2009 10:13 pm UTC, edited 1 time in total.
poxic wrote:You, sir, have heroic hair.

(Avatar by Sungura)

e^iπ+1=0
Gooder

Posts: 1969
Joined: Sun Feb 15, 2009 9:41 am UTC
Location: 54.0367˚N, 2.7961˚W; Lancaster

### The story so far...

Page 10100/101110
Spoiler:
Page 10100 has the number 101110, below the comic, in red. The comic on page 10100 is #247, but the one in the book is different from the one on the site. In the book, the time is 2:07 and therefore the guy says "207 is 3x3x23" and then in the last panel the time is changed to 14:07.

The number 101110 is a page number. That page has a small red pixel drawing, which is 23 pixels wide and 9=3x3 pixels high, and therefore contains 207 pixels. I'm not sure how this helps, but I suspect it's a clue.

Page 1111 "3 of 8"
Spoiler:
Presumably the third part of the 256 bit AES key referenced in the code on page 11 is concealed on this page. The Penny Arcade non-parody seems to exactly match comic #160, so my guess is nothing is hidden in it. The other comic, by contrast, does NOT match the original comic #153, so I'm guessing the key part is the numbers in the slide, which no longer match the diagrams for shift/invert/reverse as they do in the original.

This gives 1101 1010 0001 0000 0001 1100 1011 1100 = DA101CBC

Alright, this seems like a good time for a summary of what we know. I'm going to take the previous post and incorporate the older solutions. A red asterisk means that the code has been deciphered, although the deciphered text may not be entirely explained. A blue asterisk means some non-code puzzle has been solved. A spoiler with no asterisk means we have partial information but not a decipherment and/or complete solution. The solution credit will go to the first person who solved it in this thread.

*1. Page numbers
Spoiler:
The pages are numbered in "skew binary" whereby each digit represents a multiple of 2k+1-1.

So 10112skew would be 1*(25-1)+0*(24-1)+1*(23-1)+1*(22-1)+2*(21-1)=31+0+7+3+2=43.

Skew binary also has the property that all digits are either 0 or 1 except for the rightmost non-zero digit.
Solved by e+1=0.

*2. (last page of intro, unnumbered) 15 11 1 25 8 5 18 5 23 5 7 15
Spoiler:
These are just letters, with 1=a, 2=b, 3=c, etc., so we have, "okay here we go."
Solved by lu6cifer.

*3. (page 1) CNEG BAR BS RVTUG VA URK: RR AVAR RVTUG SVIR BAR BAR RVTUG.
Spoiler:
It uses ROT13. It translates to "PART ONE OF EIGHT IN HEX: EE NINE EIGHT FIVE ONE ONE EIGHT."
Solved by dkurth.

*4. (page 11)
Code: Select all
1 0 T A E / K E2 0 1 B S W I Y0 D E 6 S T N 8C 0 2 5 . R A P
Spoiler:
If you walk over the letters, starting at the top left, you can get the following:
10020 code 256 bit aes w/ key in 8 parts.

10020 contains the big hexadecimal code, and we have other clues labeled part n/8, so it makes sense. A 256 bit key in 8 parts should have 32 bits per part, so each part should be 8 hex digits. This matches what we saw for part 1.
Solved by yehudasa and Vhailor.

*5. (page 111) CY-O CMLROOCXN. YR M.AOGP. NRK.W ABE ,CYDRGY M.AOGP.M.BY YD.P JAB X. BR OJC.BJ.V <D.B CY JRM.O YR NRK.W ,.-P. ANN CB YD. EAPTV [[TCBO.F
Spoiler:
Simple substitution cipher, operating on all characters (letters and punctuation). It deciphers to "It's impossible to measure love, and without measurement there can be no science. When it comes to love, we're all in the dark. --Kinsey" This quote goes with comic #55: "Useless".
Solved by yehudasa.

*6. (page 1012) Dot pattern, not easily typed.
Spoiler:
Braille. It reads, "It takes more time than you expect but less than you fear." This is a reference to the above comic, #128: "dPain over dt".
Solved by FallenNicolae.

*7. (page 1111) "3 of 8".
Spoiler:
Presumably the third part of the 256 bit AES key referenced in the code on page 11 is concealed on this page. The Penny Arcade non-parody seems to exactly match comic #160, so my guess is nothing is hidden in it. The other comic, by contrast, does NOT match the original comic #153, so I'm guessing the key part is the numbers in the slide, which no longer match the diagrams for shift/invert/reverse as they do in the original.

This gives 1101 1010 0001 0000 0001 1100 1011 1100 = DA101CBC
Solved by skeptical scientist.

8. (page 10020) The comic on this page is #240, incase it's connected.
Code: Select all
662A3A35 DEF88CA7  0BDFD186 20B05684  934721F8 F64762FD03F8D76B 3FA0CB8C  2756B2D0 A9F00A1B  CFF1603E DB05426C
Spoiler:
This is the 256-bit AES cipher referenced in the code on page 11.

That comic holds a special place in Randall's heart, as he explained in the intro (and elsewhere). Also, this code seems to be the focus of several other codes in the book, so it seems important. I'm guessing that deciphering this code, when deciphered, will lead to another meetup or other real-world happening. That could mean there's a time limit on it, but hopefully Randall will have made it far enough in advance that we have some time.

Two things have changed between this comic and the original. The coordinates went from 42.39561 -71.13051 2007 09 23 14 38 00 to 42.39561 -79.13051 2007 09 23 02 38 00, and the conversation on the last panel changed completely. I'm not sure what either of these changes might mean; possibly deciphering the encrypted message might provide some clues.
Unsolved.

9. (page 10100) 101110
Spoiler:
The comic on page 10100 is #247, but the one in the book is different from the one on the site. In the book, the time is 2:07 and therefore the guy says "207 is 3x3x23" and then in the last panel the time is changed to 14:07.

The number 101110 is a page number. That page has a small red pixel drawing, which is 23 pixels wide and 9=3x3 pixels high, and therefore contains 207 pixels. I'm not sure how this helps, but I suspect it's a clue.
Unsolved.

*10. (page 10101) Sequence of stick figures posed in various ways.
Spoiler:
Simple substitution cipher, but with stick figures, a la The Adventure of the Dancing Men. The plaintext is "started with four letters but only need three what a riddle what a mystery." I'm not certain what it means.
Deciphered by skeptical scientist; still unsolved.

11. (page 10112) 0011001001011100000101100000110111100100001010100110011000010010110011
Unsolved.

*12. (page 11002) UATAQANUUNG QSICHINGNKUCHAANG CHSICHINGSICHINGNG SICHINGULUUNGUUNG CHAANGATAQANCHATAQANNG SICHINGULUUNGUUNG HSICHINGULUUNGATAQANM-SICHINGULUUNGSICHINGQSICHINGN NUATAQAN
Spoiler:
This one uses Aleut numbers:

uataqanuung qsichingnkuchaang chsichingsichingng sichinguluunguung chaangataqanchataqanng sichinguluunguung hsichinguluuungataqanm-sichinguluungsichingqsichingn nuataqan

Ataqan is the Aleut number 1, for example; siching is 4, uluung is 7 and chaang is 5. We can pick out each occurrence of an aleut number in blue:
uataqanuung qsichingnkuchaang chsichingsichingng sichinguluunguung chaangataqanchataqanng sichinguluunguung hsichinguluuungataqanm-sichinguluungsichingqsichingn nuataqan

Subsituting these gives:
u1uung q4nku5 ch44ng 47uung 51ch1ng 47uung h471m-474q4n nu1

Assuming 1337 speak, we have:
uluung qankus chaang atuung siching hatim-ataqan nul

This is Aleut for 7 3 5 6 4 6 11 nul

Translating to hex gives 735646B0. Presumably this is one of our 8 parts.
Solved by FallenNicolae.

*13. (page 11011) To: *drawing of reddit alien*
Code: Select all
GJNHIYTOTNNNBSFOEVYYVTNAQGYIUAEIEAIAEURFYVGULGBIREOUKEGEAEEPFQVQTLEDVYSRNVNJULRNAQTVZOYRVETOHRHEWSWHAGURJNORNYYZVZFDESFYIEIOPELJRERGUROBEBRLGNVNLSDKETEBI
Spoiler:
I went searching for this one on reddit and of course they already had it worked out.

First, you use ROT13 again to produce the following:
Code: Select all
TWAUVLGBGAAAOFSBRILLIGANDTLVHNRVRNVNRHESLITHYTOVERBHXRTRNRRCSDIDGYRQILFEAIAWHYEANDGIMBLEIRGBUEURJFJUNTHEWABEALLMIMSQRFSLVRVBCRYWERETHEBOROEYTAIAYFQXRGROV

Then, you remove the parts of the code which are part of Lewis Carroll's "Jabberwocky". He actually incorrectly wrote the last word (or the part of it that's there) wrong. It should be borogoves, rather than borogroves.
TWAUVLGBGAAAOFSBRILLIG
ANDTLVHNRVRNVNRHESLI
THYTOVE
RBHXRTRNRRCSD
IDGYR
QILFEAIAWHYEANDGIMBL
EI
RGBUEURJFJUNTHEWAB
EALLMIMS
QRFSLVRVBCRYWE
RETHEBORO
EYTAIAYFQXRGROV

Code: Select all
UVLGBGAAAOFLVHNRVRNVNRRBHXRTRNRRCQILFEAIAWHYRGBUEURJFJUQRFSLVRVBCREYTAIAYFQXR

Then, you have to use ROT13 again to get this:
Code: Select all
HIYTOTNNNBSYIUAEIEAIAEEOUKEGEAEEPDVYSRNVNJULETOHRHEWSWHDESFYIEIOPERLGNVNLSDKE

Then, rearrange the rows thusly:
Code: Select all
HIYTOTNNNBSETOHRHEWSWHYIUAEIEAIAERLGNVNLSDKEEOUKEGEAEEPDVYSRNVNJULDESFYIEIOPE

And then read down the columns and you get "Hey reddit I love you guys thanks for everything nine eleven was an inside job wake up sheeple"
Solved by redditors (of course).

14. (page 100000) HALF OF WHAT YOU SEEK IS HERE / AND HALF YOU'VE SEEN BEFORE
SO WHY DON'T YOU WISE UP A BIT / AND DIGG A LITTLE MORE
429C6822BE41C334BE616EFFF8B5A320

Unsolved.

*15. (page 100012) Five pixel images.
Spoiler:
These are QR codes. FallenNicolae writes:
I was able to take a picture and decode the top 3 and the bottom, but the 4th wouldn't. I'll take another later and try, but the others are:

1: Toad's Factory 2:00.776
2: Coconut Mall 2:08.147
3: DK Summit 2:03.351
4:
5: Thanks, David and Ashley.

Which I believe are Mario Kart levels (and presumably times)-- makes sense given the comic on that page.
There are QR code readers for many cellphones, including the iPhone, so if anyone can download one (or already has one) and can try to decipher the fourth code, I would appreciate it. My cellphone, unfortunately, won't work.
Solved (mostly) by FallenNicolae.

16. (page 101110) Pixel image.
Spoiler:
As I said above, I believe this is related to the factoring the time comic on page 10100.
Unsolved.

17. (various pages) Page 101010, in the upper-right corner, has "LY" in gray text. Other pages have red text in the upper-right corner, always two letters. Page 101120: IK; page 102000: GU; page 110100: EH; page 110102: DO; page 110111: CR. I'm not sure what any of this means, or if the difference between red and grey text is significant.

Unsolved.

*18. (page 110120) The start of the tenth favorite word used by Bender
The toon that went south while commanded by Ender
The number of lights that Picard said were on
And the class of the planet where Kirk shouted "Khaaan!"
The rings for the men minus rings for the elves
And the product mod ten of a fivesome of twelves
The end of a code NES gamers know
And the base used to model how quickly things grow
When they're XOR'd together the checksum is "E"
Which will tell you you've got the penultimate key
Spoiler:
The start of the tenth-favorite word used by Bender: C (for Chump)
The toon that went south while commanded by Ender: B (first battle, against Rabbit)
The number of lights that Picard said were on: 4 (Chain of Command)
And the class of the planet where Kirk shouted "Khaaan!": D class planet (Regula)
The rings of the men minus rings for the elves: 9-3=6
And the product mod ten of a fivesome of twelves: 125=25=32=2 (mod 10)
The end of a code NES gamers know: assuming you don't count select+start, A
And the base used to model how quickly things grow: e

So key 7/8 is CB4D62AE.
Solved by skeptical scientist and FallenNicolae.

19. (page 111000) 123 B *picture of an arrow hitting a wall and bouncing off*
VRDSYLRBYSMRLUVRXGCFHZWXKYNHYKLKWMCLRMFIKOZAIYXJWITOYOVN
Spoiler:
This is the last code in the book, so it's probably part 8/8, assuming they are in chronological order.
Unsolved.

Progress on the code on page 10020:
Spoiler:
Per page 11, this is encrypted with 256 bit AES, with key in eight parts. So far we have 3 parts, and a probable fourth.
Part 1: EE985118 (page 1)
Part 3: DA101CBC (page 1111)
Part 7: CB4D62AE (page 110120)
Unknown part: 735646B0 (page 11002)
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

page 10112
Spoiler:
0011001001011100000101100000110111100100001010100110011000010010110011 is 70 binary digits. Breaking this into 14 sequences of 5 digits, and converting binary to decimal, we have 6 9 14 1 12 3 15 4 5 9 19 1 5 19. Making the substitution 1=a, 2=b, etc., we get finalcodeisaes, i.e. "final code is aes". This seems rather redundant (we already knew that from page 11), but it seems to be the solution.
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

Page 100000:
Spoiler:
Could this be a reference to the AACS encryption key controversy? If so, the half we've seen before is presumably the 128 bit number 09F91102 9D74E35B D84156C5 635688C0, which goes with the number 429C6822 BE41C334 BE616EFF F8B5A320 to give us a 256-bit key. The trouble is, what is it a key TO? I'm guessing not the code on page 10200...
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

Page 100000:
Spoiler:
"09F91102 9D74E35B D84156C5 635688C0" XOR "429C6822 BE41C334 BE616EFF F8B5A320" gives "Key #5 of 8:9be32be0" when interpreted as ASCII.
operator[]

Posts: 137
Joined: Mon May 18, 2009 6:11 pm UTC
Location: Stockholm, Sweden

### Re: Puzzles from the xkcd book

I doubt that it's relevant, but on page 11102, the five green circles at the bottom are the EURion Constellation.
Kaldra

Posts: 32
Joined: Mon Apr 20, 2009 3:28 am UTC

### Re: Puzzles from the xkcd book

QR Code #4:
Spoiler:
DK Mountain (DD): 1:59.814
shaav

Posts: 1
Joined: Tue Oct 06, 2009 9:32 pm UTC

### Re: Puzzles from the xkcd book

Attached is the pattern on page 101110. I copied it by hand.
Also, 1407=3x7x67

Last edited by nerd65536 on Fri Nov 13, 2009 12:37 am UTC, edited 1 time in total.

3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679
8214808651328230664709384460955058223172535940812848111745028410270193852110555964462294895493038196
44288109756659334461284756482...

nerd65536

Posts: 39
Joined: Wed Jul 19, 2006 10:49 pm UTC

### Re: Puzzles from the xkcd book

nerd65536 wrote:Attached is the pattern on page 101110.

If red=1 and white=0...

10111110101111110111111
11111111101011110100001
10111111111111111010100
11011001001001001010111
01100101011110100000000
01101110101100111111111
10111101011011110111110
01111111111010100100001
10111111111111001101111
alxndr

Posts: 7
Joined: Sun Oct 25, 2009 1:00 am UTC

### Re: Puzzles from the xkcd book

And since the number of bits isn't divisible by 8, that doesn't seem to be the solution. Nice try though.
poxic wrote:You, sir, have heroic hair.

(Avatar by Sungura)

e^iπ+1=0
Gooder

Posts: 1969
Joined: Sun Feb 15, 2009 9:41 am UTC
Location: 54.0367˚N, 2.7961˚W; Lancaster

### Re: Puzzles from the xkcd book

e^iπ+1=0 wrote:And since the number of bits isn't divisible by 8, that doesn't seem to be the solution. Nice try though.

I know, just thought I'd get it into text in some form.

The pointers on page 1101 (comic #138) are different in the book than online.

0x4B657932
0x6F66383A
0x73CD4542

Spoiler:
The first two pointers spell out "Key2of8:", so 73CD4542 is our second key.
alxndr

Posts: 7
Joined: Sun Oct 25, 2009 1:00 am UTC

### Re: Puzzles from the xkcd book

That, however, does help!

Which means that so far we have:
Spoiler:
Part 1: EE985118 (page 1)
Part 2: 73CD4542 (page 1101)
Part 3: DA101CBC (page 1111)
Part 4: 735646B0 (page 11002)
Part 5: 9BE32BE0 (page 100000)
Part 7: CB4D62AE (page 110120)

The previously unknown part is probably part 4, assuming that the parts are in numerical order, which the rest seem to be.

Part 6 would then be from this and part 8 would be from #19 in the summary post.
poxic wrote:You, sir, have heroic hair.

(Avatar by Sungura)

e^iπ+1=0
Gooder

Posts: 1969
Joined: Sun Feb 15, 2009 9:41 am UTC
Location: 54.0367˚N, 2.7961˚W; Lancaster

### Re: Puzzles from the xkcd book

Thoughts on page 101110:
Spoiler:
There is far too much information embedded in the pattern to be meant as raw binary data, and there is also a lot of red squares, so those seem to have some special meaning to the code.
An interesting fact is that counting the number of continuous red squares (separating by white ones), every number is strictly less than 16 (15 occurs two times when read horizontally, 13 one time when read vertically). This - and the thought mentioned above - suggests that this might be on the right track for solving the code.
These numbers as a sequence horizontally is (reading from left to right and wrapping down - and with the rule that two white squares adjacent to each other implies a sequence of length 0):
1516f1412f1102201010101113201141000000002312a412450a11010002c024
which, while it is not ASCII, looks pattern-like and also coincidentally has length 64.
operator[]

Posts: 137
Joined: Mon May 18, 2009 6:11 pm UTC
Location: Stockholm, Sweden

### Re: Puzzles from the xkcd book

Now, I know nothing about cryptography, but I am good at spotting patterns. I think there's a chance you're on to something with that.

operator[] wrote:Thoughts on page 101110:
Spoiler:
These numbers as a sequence horizontally is (reading from left to right and wrapping down - and with the rule that two white squares adjacent to each other implies a sequence of length 0):
1516f1412f1102201010101113201141000000002312a412450a11010002c024
which, while it is not ASCII, looks pattern-like and also coincidentally has length 64.

Maybe that's no so much of a coincidence after all:

Spoiler:
1516f141 2f110220 10101011 13201141 00000000 2312a412 450a1101 0002c024

Could this be the 8 characters of the next key, encoded somehow?

Lukeonia1

Posts: 34
Joined: Thu Mar 13, 2008 7:30 am UTC

### Re: Puzzles from the xkcd book

Spoiler:
I'm pretty sure this would be the opposite of Occam's Razor
Anyone apply the game of life to puzzle 101110?
Xami

Posts: 72
Joined: Tue Sep 29, 2009 8:29 pm UTC

### Re: Puzzles from the xkcd book

Xami wrote:
Spoiler:
I'm pretty sure this would be the opposite of Occam's Razor
Anyone apply the game of life to puzzle 101110?

Wait, what? Do you know something the rest of us don't?

Lukeonia1

Posts: 34
Joined: Thu Mar 13, 2008 7:30 am UTC

### Re: Puzzles from the xkcd book

I just tried that - the results looked pretty random.
I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

skeptical scientist
closed-minded spiritualist

Posts: 6135
Joined: Tue Nov 28, 2006 6:09 am UTC
Location: San Francisco

### Re: Puzzles from the xkcd book

Lukeonia1 wrote:
Xami wrote:
Spoiler:
I'm pretty sure this would be the opposite of Occam's Razor
Anyone apply the game of life to puzzle 101110?

Wait, what? Do you know something the rest of us don't?

Skep has it - I learned about it in a highschool programming course. Also, I had no real hopes of this generating anything useful.
http://en.wikipedia.org/wiki/Conway's_Game_of_Life
Xami

Posts: 72
Joined: Tue Sep 29, 2009 8:29 pm UTC

### Re: Puzzles from the xkcd book

operator[] wrote:
Spoiler:
These numbers as a sequence horizontally is (reading from left to right and wrapping down - and with the rule that two white squares adjacent to each other implies a sequence of length 0):
1516f1412f1102201010101113201141000000002312a412450a11010002c024
which, while it is not ASCII, looks pattern-like and also coincidentally has length 64.
Spoiler:
It turns out I miscounted... The actual sequence is
1516f1410002f1102201010101132011410000000023120a412450a11010002c024,
which is 67 letters and probably not the correct one to look for patterns in. I think the method may be correct though, so I'll continue looking at it.

Xami wrote:
Spoiler:
I'm pretty sure this would be the opposite of Occam's Razor
Anyone apply the game of life to puzzle 101110?
Spoiler:
If not the regular Game of Life, it is possible other rules from Cellular Automaton would work, as in xkcd 505. Look up the page/comic number at MathWorld.
operator[]

Posts: 137
Joined: Mon May 18, 2009 6:11 pm UTC
Location: Stockholm, Sweden

### Re: Puzzles from the xkcd book

page 10020
Code: Select all
772A3A35 DEF88CA7  0BDFD186 20B05684  934721F8 F64762FD03F8D76B 3FA0CB8C  2756B2D0 A9F00A1B  CFF1603E DB05426C

I found a mistake in a previous post; the first 2 characters are 77 in the book not 66
also on page 101110
nerd65536 wrote:Attached is the pattern on page 101110. I copied it by hand.
Also, 1407=3x7x67

Spoiler:
check page 10100 and there is a red page number referring to this page; also on 10100 is a comic about factoring the time, which is different from the original. ( http://xkcd.com/247/ ) The factored time from the first panel is 3x3x23, which is the same as 9x23, which is the "height by width" of the image that nerd65536 copied for us

finally page 101012:
Spoiler:
the sheet music is changed from http://xkcd.com/389/
otterfiend

Posts: 1
Joined: Sat Oct 31, 2009 9:02 am UTC

### Re: Puzzles from the xkcd book

otterfiend wrote:
nerd65536 wrote:Attached is the pattern on page 101110. I copied it by hand.
Also, 1407=3x7x67

Spoiler:
check page 10100 and there is a red page number referring to this page; also on 10100 is a comic about factoring the time, which is different from the original. ( http://xkcd.com/247/ ) The factored time from the first panel is 3x3x23, which is the same as 9x23, which is the "height by width" of the image that nerd65536 copied for us

Now that doesn't sound like a coincidence. Question is, what does it mean?

otterfiend wrote:finally page 101012:
Spoiler:
the sheet music is changed from http://xkcd.com/389/

Spoiler:
The music has been shortened by two bars. Dunno if it means anything though.

Lukeonia1

Posts: 34
Joined: Thu Mar 13, 2008 7:30 am UTC

### Re: Puzzles from the xkcd book

Two thoughts on 101110,

Spoiler:
Since the puzzle deals with the number 207, I looked up comic 207. It has a rule for dealing with a 2-dimensional pattern of floor tiles. I'm not sure how it might be interpreted in this context, though.

Spoiler:
operator[] wrote:If not the regular Game of Life, it is possible other rules from Cellular Automaton would work, as in xkcd 505. Look up the page/comic number at MathWorld.

Wolfram Rule 34:
Rule 34 is an Elementary Cellular Automaton that operates on a 1-dimensional array.
It slides a window, 3 elements wide, across the array, looks up the contents of the window in the definition of the rule, then outputs a new element.

Rule 34 is not symmetric, so it matters whether you read left-to-right or right-to-left, and a 2D array can be read in a number of different directions. It seems someone could write a simple program to try Rule 34 on our array.

3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679
8214808651328230664709384460955058223172535940812848111745028410270193852110555964462294895493038196
44288109756659334461284756482...

nerd65536

Posts: 39
Joined: Wed Jul 19, 2006 10:49 pm UTC

### Re: Puzzles from the xkcd book

Regarding the puzzle on page 11:
Spoiler:
For what it's worth, the order the block is walked in is the Hilbert curve used to lay out the IP block map.
jerith

Posts: 1
Joined: Tue Nov 17, 2009 3:22 pm UTC

Next