
Nobody knows how to cite 4chan mathematicians who solved an interesting problem - cabraca
https://twitter.com/adversariel/status/1054811880919834634
======
tokai
It is a fun little event that something posted on 4chan is used in a research
paper.

But that nobody knows how it should be cited is just plain wrong. They should
maybe contact their research library and get a introduction to citing. All
citation styles I know of can handle web citations. Anonymous authors is
nothing new either. And you have things like the internet archive or
Webcite[0] to make sure the web document doesn't disappear. Else it could be
cited as personal communication, which usually covers direct communication,
but can also be used for nonarchived discussion groups.

The reluctance to cite a source because it's not a peer reviewed research
paper, is bordering on cargo cult science. As if going through the motions of
scientific publishing should somehow elevate arguments to truth.

[0][https://www.webcitation.org/](https://www.webcitation.org/)

~~~
rspeer
It's not that nobody _knows_ how to cite it, it's that nobody _wants_ to cite
things from outside of academia, perhaps because it lowers their own perceived
prestige.

I have seen this in computational linguistics where people frequently don't
cite their data sources, which often come from outside of the field or outside
academia altogether. Instead they put a link to a webpage in a footnote, which
does nothing for assigning credit.

Reviewers don't take anyone to task for it, because they do that too.

For a while, there was a collection of multilingual word counts over
OpenSubtitles that everyone was using, and you would acquire it from the
OneDrive of the pseudonymous blogger "Hermit Dave". Many people put the link
to his blog in a footnote, but I think I was the only person to come up with a
citation for (Dave 2011).

People don't even cite Google Books Ngrams and that's got a real paper [1].

[1] Lin, Y., Michel, J.-B., Aiden, E. L., Orwant, J., Brockman, W., and
Petrov, S. (2012). Syntactic annotations for the Google Books Ngram Corpus.
Proceedings of the ACL 2012 system demonstrations, 169-174.

~~~
throwawaymath
To give you a counterpoint, I've read plenty of computer science and
mathematics papers where someone cited an arXiv paper by an obscure or unknown
researcher. I've even seen blog posts and email correspondence cited. In fact,
in one of my own papers I cited an unpublished manuscript which you can't even
find on the internet - you have to personally contact the author, who hasn't
touched the thing in the last 25 years. For all intents and purposes, this
manuscript - while valuable - only exists in the tribal folklore of the
research community. But it's still cited and most active people in the field
probably have a personal copy of it on their hard drive.

~~~
eindiran
I think the difference is that arXiv papers don't have the same perceptions of
low prestige attached as a random blog or a 4chan thread does. The issue isn't
that the work is (yet) unpublished or that its obscure: its that it is from
outside academia or traditionally prestigious sources.

~~~
romwell
>academia or traditionally prestigious sources.

You can't really put ArXiV and "traditionally prestigious sources" in the same
sentence. Any crackpot can (and does) post on ArXiV.

The reason why I'd be more comfortable citing a paper on ArXiV than a random
web page (as a mathematician):

1\. ArXiV is _the_ archive for papers. You put something there, it's not going
away. You can't even remove your own paper once you make it public there[1].
It's a reliable place I can refer people to.

Personal websites? Well, my own very reliable academic web page has been
removed by sysadmins without notice after graduation because "we don't
maintain accounts".

2\. Unrelated content. ArXiV won't have it - unlike, say, the 4chan thread in
question. Do I really want to explain to people that I wasn't citing getting
"14 * 14! derps out of the way"?. Not to mention ads, memes and NSFW content -
which is also there[2][3]

\----------

The other reasons are less important, but are still valid:

3\. Presentation. Something on the ArXiV probably is formatted and structured
like a readable paper; there are baseline expectations. Reading someone's
_scratchwork_ is borderline painful, and a proof on a webpage is usually just
that.

Compare [3] to a rewrite[4] - which one is easier to understand at a glance?

4\. Reputation. This is different from "traditional prestige". The reputation
of ArXiV is that most of the people who do serious work put it there. Most of
the people produce nonsense (possibly including yours truly) also put it
there, but the probability of any work having been done by someone who is
willing to put effort into it goes down dramatically if the work is not on
ArXiV.

5\. Signaling. Since it's so easy to post there, any work _not_ ArXiV is
signaling "I don't care about my work being available to other people in the
field". Why one read something that the author doesn't _want_ them to? If they
did, they'd put it on the ArXiV.

6\. Attribution. A result on ArXiV makes it easy for me to attribute the
result to _someone_. A thread on 4chan? Do I attribute it to everyone who
participated? A single anonymous author?

\----------

In short: people give _credit_ to blackboard scribbles and napkin proofs that
came out of discussions at conferences, but you won't see "4th beer coaster,
such-and-such conference banquet, 2018" as something that people _cite_.

A proof on 4chan is somewhere in the same category.

\----------

The disclaimer here is that this applies mostly to new results in mathematics.
Old results are not necessarily available online, and often we don't have a
choice. Practices in other fields might be different.

\---------

[1] [https://arxiv.org/help/withdraw](https://arxiv.org/help/withdraw)

[2][https://warosu.org/sci/thread/S3751105#p3751197](https://warosu.org/sci/thread/S3751105#p3751197)

[3][http://4watch.org/superstring/](http://4watch.org/superstring/)

[4][https://docs.google.com/viewer?a=v&pid=forums&srcid=MTUwMTUx...](https://docs.google.com/viewer?a=v&pid=forums&srcid=MTUwMTUxMjExNDk4NTk5NjY5OTkBMDMxNDgwMTA5ODA5OTYyNzcyNDQBdlNFMnM3eTVCUUFKATAuMQEBdjI&authuser=0)

~~~
Nomentatus
It's up to professors. I've had very important work taken by professors and
published by them from my websites without attribution - even my own old
professors! They think theft is fine if you aren't a fellow pirate,
apparently. Arxiv is used by fellow pirates, so it's off limits, on this view.

~~~
zmw
That sounds mighty weird, and honestly the statement has certain
characteritics that trigger my crackpot alarm (don’t take it personally)... If
what you say is true, it’s not like you don’t have recourse — you can write to
the publication’s editorial board, or report to your department or
institution’s academic disciplinary body (of course, that’s after you have
contacted whomever you’re in dispute with; it’s okay, and I’ve had people cold
emailing me about my preprint, asking me to mention their only somewhat
related and by no means appropriated work...) Also, if you produced whatever
result when you were working for a professor, they can publish it under their
name (it’s nice to at least have you on the author list, of course), you don’t
revoke their right just by publishing it on your own website. Anyway, whining
on HN is the about least useful thing you can do.

~~~
Nomentatus
This is common stuff, and good luck on prompt action! No, I wasn't working for
a prof - but note that you yourself just accept that work including ideas can
be published by a prof without attribution to the discoverer! That tells us
all where the academic mindset is. My noting is your whining, I gather. One
can't tarry on life's path to upbraid all the assholes in the world, and legal
redress is well out of reach of most of us. One can note it to warn others,
and move on.

------
dijhrykl
For those not familiar with the series in question, there's a reason why, if
you're going to choose a TV series to discuss permutations, you'd choose
Haruhi.

"The Melancholy of Haruhi Suzumiya" is a 14-episode anime adaptation which
aired in 2006. Unusually, it broadcast its episodes not in chronological
order, but in a mixed order, but for good theatrical reason; the series
comprises a main plot arc, and various self-contained episodes which
chronologically occur after it. Rather than have the climax of the series come
halfway through, the self-contained episodes are distributed in between the
episodes of the main plot arc. It sounds mad, but it actually worked very
well.

This idiosyncrasy was explicitly referenced by the episodes themselves: the
"next episode" preview at the end of every episode has one of the characters
say "The next episode is episode X", then another character says "Wrong! The
next episode is episode Y", where X and Y are the numbers according to
broadcast and chronological order.

Amusingly the story gets more complicated from here. After the series was
unexpectedly popular in the anglosphere, it got licensed for an official
release. After the contract was signed and it was too late to change it, the
company which licensed it noticed the contract had a stock clause in it
requiring the episodes to be released on DVD in chronological order. They were
unable to get this changed, whereas the strong fan preference was for the
broadcast order. As a partial workaround, I recall they released a special
edition with the same episodes on two sets of discs: one in broadcast order
and one in chronological order.

But the DVD "chronological order" isn't quite chronological either; one of the
episodes is a show-within-a-show, a film made by the characters of the series.
This happens chronologically late in the show, but it is the first episode in
both the broadcast and DVD order (which makes for an extremely confusing
introduction to the series).

So there are at least three different plausible ways to watch the series:
broadcast order, chronological order, and DVD order (which is almost like
chronological order but not quite). This absurd legacy makes the series rather
the obvious choice for discussing permutations of episodes. (My own preference
is for yet another permutation: broadcast order, but with the aforementioned
first episode moved to before the 12th episode, which relates to it.)

~~~
PurpleRamen
> "The Melancholy of Haruhi Suzumiya" is a 14-episode anime adaptation which
> aired in 2006.

The first version to be correctly. They later added another 14 episodes, but
instead of calling it a new season, they mixed in the new episodes between the
old episodes and rebroadcasted it as one complete series.

As a special "joke", they also had a timeloop-story spanning multiple
episodes, with each episodes telling the same story with slight changes in the
story, and individual art-style, meaniung each episodes was produced new not
just recycled from the first episode. The "joke" with this story was, that of
the 14 new episodes, the timeloop-story filled 8(!) episodes and went under
the funny name "Endless Eight". I think someone was fired himself for this.

~~~
meesles
The Endless Eight was widely regarded as a rite of passage in anime spheres. A
lot of people would end up skipping the second half after they realized what
was going on. Great show, and as far as I know the only one to have attempted
something like this.

I personally didn't like it, it just seemed soooooo long. The only redeeming
factor (in my opinion) is that Suzumiya Haruhi is outlandish enough for it to
be the perfect vessel for such an experiment.

~~~
Laforet
The act did have some thematic significance with the movie release in 2010, in
which the time loop incident is revealed to be a major reason why the movie's
events took place.

Besides, it's a little harder to skip all eight episodes in the original
weekly broadcast not knowing when the loop will end, so viewers are more or
less forced into the cycle.

------
ASipos
Come on, this is a myth. I work in math and it is not at all unusual to cite
informal sources.

Also, someone should inform Greg Egan:
[http://www.gregegan.net/SCIENCE/Superpermutations/Superpermu...](http://www.gregegan.net/SCIENCE/Superpermutations/Superpermutations.html)

~~~
empath75
If you click through the links, he's in the google groups thread talking about
it.

~~~
ASipos
Thanks! For those interested, the link is
[https://groups.google.com/forum/m/#!topic/superpermutators/j...](https://groups.google.com/forum/m/#!topic/superpermutators/j5y24bOemiM)

------
mpiedrav
An "academically correct" solution (i.e., not to taint the prestige of a
scholar who cites the solution) would be to cite a real, proxy scholar who
checks the solution, but gives all credit to the anonymous 4chan user.

Scientists often abhor citing from blogs, forums, and Wikipedia, as those
publications "are not peer-reviewed by trustworthy professionals".

~~~
qubax
> Scientists often abhor citing from blogs, forums, and Wikipedia, as those
> publications "are not peer-reviewed by trustworthy professionals".

Which is sad because most peer-reviewed material are not trustworthy either.

[https://bigthink.com/neurobonkers/believe-it-or-not-most-
pub...](https://bigthink.com/neurobonkers/believe-it-or-not-most-published-
research-findings-are-probably-false)

[https://journals.plos.org/plosmedicine/article?id=10.1371/jo...](https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0020124)

It's worrying that academia is slowly turning into a rigid "appeal to
authority" church rather than a space for truth and inquiry.

~~~
Certhas
Peer review is a base level quality check, not a correctness check in most
disciplines.

It provides value, indeed most of my papers have been improved by going
through peer review. But it's good to be conscious of what it can and can not
do.

One thing that it does do is signal intent. It signals that you are willing to
engage with the expert community, and specifically their feedback and
criticism.

Finally, there is of course a fallacy in saying "not trustworthy either". If
99% of random blog posts are wrong, but 60% of published papers are wrong,
then a random paper is 40 times more likely to be correct than a random blog
post and it's perfectly sensible to be hesitant about citing the latter.

Finally, scientists have always cited outside of traditional sources and
continue to do so [1]. I see no evidence for your assertion that "appeal to
authority" has become more prevalent or important than it used to be. With all
the ongoing open science initiatives it's rather the opposite.

[1] Personal communication with various scientists, 2018

~~~
neuromantik8086
> Peer review is a base level quality check

Ideally this is true. At the worst though, you'll end up with a peer reviewer
that gets pedantic or one who's a member of a citation cartel [0] that demands
that you cite his/her friends papers unnecessarily as a quid-pro-quo leading
to publication. It's difficult to say how common this is in practice since
academia is generally terrible about self-reflection, but I observed
concerning evidence of this when I was still in science. In some fields at
least, there's ample evidence [1] that peer review provides inadequate QC
controls for methods sections, making it literally impossible to replicate
results due to entire processing steps being omitted. This is why post-
publication services such as PubPeer have become more and more relevant, since
it has become obvious as time has elapsed how woefully inadequate the initial
screening process is.

[0]
[https://academia.stackexchange.com/questions/81261/reviewer-...](https://academia.stackexchange.com/questions/81261/reviewer-
recommending-citation-of-certain-papers-of-specific-group-of-authors-ma)

[1]
[https://www.ncbi.nlm.nih.gov/pubmed/22796459](https://www.ncbi.nlm.nih.gov/pubmed/22796459)

~~~
Certhas
It's good to keep in mind that reviewers do not make the decision. They
recommend the decision. The Editor, who knows the identity of the reviewer,
can see if a reviewer is asking for unreasonable citations.

So while this definitely does happen (and to different degrees in different
fields) there are some checks and balances, too.

~~~
neuromantik8086
True, and your overall point (that it is better than the alternative; i.e.
viXra) stands. It's really one of those things where ymmv depending on the
field- I just happened to notice a somewhat disheartening tendency for those
sorts of horse trading practices to creep in, which is ultimately one of the
major reasons why I left science.

I could be naive, but my impression was that there are almost too many degrees
of freedom in the peer review process that could allow for this kind of
chicanery, and that it would almost be preferable to have criteria for
acceptance laid out in advance (i.e., exactly what steps, metrics, and citable
articles were necessary) and use those the way an actuary would. In some ways
I almost think that practices like preregistration serve as a better first-
pass indicator of whether or not research is publishable.

~~~
Certhas
Completely agreed. I think the system is ripe for an overhaul, and has many
problematic aspects. We'll see how it goes, after all it doesn't look too bad
with the open access revolution.

I personally would like more use of pre-registration (there is something about
that on the front-page right now. But also I think deanonymzing peer review
and publishing the reviews along with the papers could be very interesting.
Obvious drawbacks as well of course but I think it has potentially massive
upsides.

------
ortusdux
The Haruhi problem reminds me of De Bruijn sequences, aka why I don't trust 5
button keyless car entry systems. Fords keypads do not have return keys,
delays, or attempt limits. A 3125 button sequence can guarantee you will
unlock the door. It would take about 10-20 minutes for someone who has
practiced to break in. Someone this year made a bot that did it in about 5
minutes.

[https://en.wikipedia.org/wiki/De_Bruijn_sequence](https://en.wikipedia.org/wiki/De_Bruijn_sequence)

[https://hackaday.com/2018/06/18/opening-a-ford-with-a-
robot-...](https://hackaday.com/2018/06/18/opening-a-ford-with-a-robot-and-
the-de-bruijn-sequence/)

~~~
strictnein
You're worried about someone standing next to your car for 10-20 minutes
pushing buttons and not messing up a 3125 number combo on a keypad with almost
no tactile feedback?

~~~
codys
The comment you're replying to contains:

> Someone this year made a bot that did it in about 5 minutes.

It's also the case that it's plausible one can interrupt & resume the sequence
(at the cost of 4 extra button presses per interruption).

~~~
strictnein
Sure, but it's kind of silly. There are far, far simpler ways to get into a
car than bringing a robot with you.

~~~
pbhjpbhj
Do they give you on-going [presumably] secret access?

------
montenegrohugo
This is fantastic. Imagine having to cite "Anonymous user on 4chan" on your
paper.

I'd probably just do it for the novelty (who else can say they have a more
unusual source??)

~~~
RowBoat6123
Bill Thurston cited personal communication with himself, which is a pretty
unusual source.

~~~
mietek
Inevitably, I’m going to have to ask for a reference.

~~~
chrislipa
He used to sit on the floor of his office with the lights off under a giant
moving box and brainstorm math.

Reference: personal communication

------
maze-le
This might be a ghost discussion. I have worked in scientific publishing for
quite some time and have seen citations in the form of:

* personal correspondence

* emails

* facebook profile pages

and my personal highlight

* google search queries (I kid you not)

All of these citations actually occured in scientific journals. I assume
Nicolas Bourbaki was also cited several times, without anyone caring about
"academically correct" citation rules.

[0]:
[https://en.wikipedia.org/wiki/Nicolas_Bourbaki](https://en.wikipedia.org/wiki/Nicolas_Bourbaki)

~~~
internet555
Wow I did this in high school but I got in trouble

Citations:

-Google

-Nicolas Bourbaki

-Rob’s Facebook wall

-My friend in gchat

~~~
saagarjha
Hopefully you got in trouble for your poor citation format, not your sources.

~~~
internet555
I got in trouble for everything! And everyone hated me

------
btrettel
I would cite the wiki with a note in the citation that the wiki was a copy of
the 4chan thread. And I'd put a copy on an web archive service. WebCite was
mentioned in the Twitter thread:
[http://www.webcitation.org/](http://www.webcitation.org/)

If this isn't credible enough for most academics, then I think they have their
priorities wrong. I want to cite the best work, not just work that looks good
superficially. I assume that the claim that this is the best known lower bound
is true. In that case, if I am writing a relevant paper, it's my duty to cite
the result regardless of where it came from as far as I am concerned.

Edit: Same sentiment in this post a few minutes before mine:
[https://news.ycombinator.com/item?id=18292438](https://news.ycombinator.com/item?id=18292438)

------
adamrezich
If anyone's trying to figure out what the "Haruhi Problem" is, logically,
because it took me awhile to grok:

You have a `n`-episode show, and you want to watch every episode in every
possible order. However, if one series-watch-through ends with episode `x` and
the next series-watch-through in sequence begins with that same episode `x`,
you don't have to watch episode `x` twice in a row. Given these constraints,
how do you find the "ideal" way to watch through the entire series, in all
possible combinations, in the shortest number of episodes?

~~~
theogravity
The "Haruhi" part refers to a novel/manga/anime/game series titled "Haruhi
Suzumiya", where the anime episodes were purposely aired out of order.

------
firdak
Looking at this from the other side, if a non-mathematician "solves an
interesting problem", is there a recommended way to make the solution public?
Something better than posting to 4chan?

Is it possible to publish a result properly if one is not a mathematician and
not affiliated with an institution?

~~~
JorgeGT
You can send it to a journal as a private individual, but probably a better
way would to post a manuscript on arxiv.org, and once it generates certain
buzz (if the problem is interesting and well solved) then either submit it to
a journal yourself or partner with other mathematician to polish it, etc. and
then submit.

~~~
whitecream
To be able to submit to arXiv, one needs to be endorsed by someone in the
domain, which could be a potential hurdle for someone not in academia. (and
I'm not about to suggest viXra as a way to get around that)

~~~
Grue3
Yeah, I actually used to be a math post-graduate and have a draft of a paper
with an interesting result, so I wanted to publish it but I had no idea how to
get "endorsed". This was like 10 years ago and I switched to a career in
programming so I doubt I'll even understand my own proof now.

------
jhallenworld
Back in the 90s there was the same discussion involving citing USENET news
postings. I would suggest that some of the news postings were better peer
reviewed than Journal articles. There was certainly a time when the top
academics of certain fields were USENET junkies.

I suppose hacker news is the most recent equivalent.

~~~
creative1thr
>I suppose hacker news is the most recent equivalent.

It looks like 4chan may be the most recent equivalent : )

------
ncmncm
The authors of FFTW published a paper about their computational method, an
early example of "cache-oblivious" array traversal order. (In this method,
uses of elements noodle around in small areas, getting a free locality boost.
Typically they use a Hilbert or Peano path.) They refused to cite Todd
Veldhuizen, who had done it (with plenty of publicity) a year before. They
refused to discuss why, but it is apparent that it was because Veldhuizen had
published in Dr. Dobb's Journal of Computer Orthodontia ("Running light
without overbyte").

------
mohammedbin
Something I somehow doubt too many of you would know but 4chan, despite being
considered an unsavoury place because of certain subsections of it (which I'm
not proud to admit I visit to learn what "the other side" is talking about),
has a lot of great communities as well and I usually find the discussion
quality there better than reddit.

Also, in the context of this thread, 4chan is an ephemeral site so there is no
such thing as link to content.

~~~
krustyburger
What are some of the worthwhile communities?

~~~
hood_syntax
If you are a video game enthusiast, particularly of a niche genre, /vg/ can be
a good place. I'm really into roguelikes, so I visit the '/rlg/' thread around
once a week to see what's going on and potentially get some advice if I'm at a
tricky part in a run or need to make a decision about where to take my
character.

Standard disclaimer applies about 4chan. If you're thin-skinned, you may find
it not worth the trouble. Just don't engage with the trolls and you'll be
fine.

~~~
VLM
/tg/ is truly excellent for non-video game discussion (board games, card
games, w40k, MtG, etc). They are a bit opinionated much like /vg/ and I'd
agree, thin skinned people will be happiest if they stay away. For example
there is little love for Paizo/Pathfinder on /tg/ (although there are some
fans...)

------
Varcht
The Anon's Dilemma. To dox, or not to dox oneself, as an anime fan, in order
to advance career.

------
scott_s
I have co-authored a paper where we cited the solution in a StackOverflow
post. See reference 1: [https://www.scott-
a-s.com/files/debs2017_daba.pdf](https://www.scott-
a-s.com/files/debs2017_daba.pdf)

I noticed that in a paper written by different authors, rather than citing the
StackOverflow post when discussing that solution, cited our paper above.

------
manfredo
Isn't board name (/o/, /vg/, etc.) and post ID (the number people talk about
when they say "trips", "dubs", and so forth) enough to uniquely identify a
4chan post?

------
pfortuny
Total non-issue:

“The following proof was found in the 4chan web site (URL at the end), without
any attribution...”

------
CogitoCogito
Some people here talk of the difficulty of citing sources that may disappear.
This can easily be solved by just reproducing the proof (and stating
explicitly that that is what you're doing and providing references to the
ephemeral sources as they exist when you write it). Of course you should clean
up the proof as much as possible. This only needs to be done once since others
can site your reproduction of the proof if they have similar misgivings.

------
SilasX
Also, didn't 4chan invent SleepSort?

[https://www.cs.princeton.edu/courses/archive/fall13/cos226/l...](https://www.cs.princeton.edu/courses/archive/fall13/cos226/lectures/52Tries.pdf)

tl;dr: Iterate through each value v and spawn a process that waits v seconds
before writing itself as output.

Edit: Earliest HN discussion:
[https://news.ycombinator.com/item?id=2657277](https://news.ycombinator.com/item?id=2657277)

------
mschuetz
In real-time rendering, a lot of innovation and state-of-the-art is published
in non-peer-reviewed conference slides by companies, or blog posts by non-
academic individuals.

These should absolutely be cited if you as a researcher are convinced they are
correct. There is no good reason not to.

------
pjc50
A surprising amount of effort goes into maintaining uniform citation formats
for papers. Bibtex is one of the various tools built to manage them. They're
effectively the original hyperlinks, on paper.

------
maerF0x0
Naive thought:

Some undergrad or masters should do some work to validate the work and write a
paper about the validation. Then they'll be cited by anyone who wants to use
the 4chan thing

------
golergka
Well, as long as people quote Broom Bridge for quaternion multiplication, I
don't see any reason why they couldn't quote 4chan as well.

------
SilasX
Oh man, I wish a mainstream publication would pick this up, it would be a
great /r/notTheOnion submission.

------
thatindiandude
I believe you should cite by referencing with the meme of your choice

------
dbcooper
A 4chan poster told me that it was the Russian guy who turned down the Fields
Medal (Grigori Perelman?). Take that with a grain of salt.

~~~
acqq
...who previously jumped out of the plane in the middle of the night over the
forest with the blackmailed money, badly functioning parachute and survived,
contrary to common sense. Because the posters there wouldn't try to troll.
Yes, take that with... whatever.

------
snvzz
What's so hard about attributing it to Anon?

------
izzydata
One problem with linking to anything on 4chan is that it will be purged within
the day and no longer available.

~~~
huntie
You can always make use of the various archive sites. The thread referred to
is from 2011, and is available on warosu[1]. It is worth noting that 4chan
keeps its own 2 week archive now as well.

[1]
[https://warosu.org/sci/thread/S3751105#p3751197](https://warosu.org/sci/thread/S3751105#p3751197)

------
mathiscool
Anyone remember "Good Will Hunting"?

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flatline
Isn’t this result in every introductory combinatorics textbook?

~~~
flyingfences
You're misunderstanding the problem. It's not a question of the number of
permutations. It's a question of the total number of episodes that must be
watched to have seen all possible permutations.

~~~
Izkata
Not sure why you're grey; you are correct about why it's not introductory.

Overlap between permutations is why it's not as simple as it first sounds. For
example, to borrow the wiki example, "121" includes both "12" and "21"
permutations.

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CPLX
Also lending strong support for the infinite number of monkeys theorem.

~~~
Notorious_BLT
I think you misunderstand the population of 4chan. Across its diverse boards,
there's all kind of people, and they don't fit into a single mold. For
example, all kind of skilled laborers and handy homeowners, many with
families, frequent the /diy/ board. The technology board /g/ is host to a lot
of talented, high-earning programmers mixed in with tinkerer types. /toy/ is
full of all kinds of folks, from teenagers with a few anime figures to parents
with children, the only commonality being liking some kind of toys.

A lot of people who use it simply like the lack of filters or reputation that
anonymity provides. A post doesn't come with the baggage of a username that
people can hunt through, so it can really only be judged by its content, not
by the reputation (good or bad) of its author.

Just because 4chan shows up in the news when its users are stirring up trouble
doesn't mean its all a bunch of edgy teens. Even if thats how it began, an
edgy teen from 4chan's inception is now old enough to be a part of the adult
workforce.

~~~
throwaway27940
Yeah, what you said was true _maybe_ five years ago. There _used_ to be quirky
geek types being ironic all the time and making cool stuff. When I left though
it was all Nazis and people who somehow stand Nazis 'interjecting' every few
comments about the IQ of black people or evil SJWs. This can drain even the
kindest, strongest soul. Even moot got tired of it and sold it to that
Japanese con man.

~~~
swebs
Huh? I just looked through the /diy/ board catalog and saw nothing like that.

[http://boards.4chan.org/diy/catalog](http://boards.4chan.org/diy/catalog)

~~~
newen
Mention you are black or post a picture hinting you are non-white and you'll
see them crawl out of the woodwork.

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lemoncucumber
This tweet is misleadingly worded. The solution was not posted on 4chan, but
rather by an anonymous user on a “wiki mainly devoted to anime” as the
original tweet quoted by this tweet makes clear.

~~~
rtkwe
The original tweet is somewhat confused though too because the linked wiki is
an archive/summary of a thread on /sci/ which is one of the 4chan message
boards. It's copied there because of the ephemeral nature of posts on the
actual boards so you can't provide a permanent link, thus linking to the next
best source seems the best choice.

~~~
lemoncucumber
That makes more sense, thanks for the clarification. The tweet saying that it
was originally posted on a "wiki" and then linking to a wiki made me think
that that wiki was the actual source.

