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An Anonymous Online Anime Fan Solved A Problem That's Been Eluding Mathematicians For Decades
IFL Science ^ | 10/25/2018 | staff

Posted on 10/30/2018 6:55:18 PM PDT by Eddie01

You may not have heard of The Melancholy of Haruhi Suzumiya, but, among anime fans at least, it’s a pretty big deal. Originally a series of light novels, it follows the adventures of typical high schooler Kyon and the time-travel alien ESP club he is forced to help create by his beautiful if eccentric friend, the titular Haruhi. Since its original run in 2003, it has spawned 10 additional volumes, a film adaptation, several video games, and even its own religion, Haruhiism.

It was first adapted into an anime back in 2006. The show only lasted three months but there was a twist: it was aired in nonlinear order. When the DVD was released, it had been reordered again. And, in a show featuring time travel, philosophical paradoxes, and paranormal phenomena, neither were necessarily the definitive order to watch the series.

Which led to a problem: What is the quickest way to watch the series in every possible order?

A few years ago, one anonymous 4chan poster set out to solve this puzzle. The person claimed to have worked out a lower bound for the answer – watch fewer episodes than that, and you’ve no hope of seeing the series in every order.

Crucially, they offered a proof – and, in doing so, they provided the world with an answer to a problem that had eluded mathematicians for a quarter of a century.

In mathematical terms, the Haruhi problem, as it’s become known, asks the following: What is the shortest possible length of a superpermutation of n elements?

Given a set – a collection of things, or elements, like “natural numbers less than 4” or “colors on the US flag” – a permutation basically means some order those things can be listed in. So one permutation of “natural numbers less than 4” is 123. Another is 312.

A superpermutation, however, is a string containing every possible permutation of a set. One superpermutation of natural numbers less than 4 is 123121321, as it contains each of the six possible orderings of the numbers 1, 2, and 3.

There are six possible permutations of three elements. This superpermutation contains them all. That’s fine for small sets, but the lengths of these superpermutations can get really big, really fast. In fact, by the time you have five numbers in your set, the shortest superpermutation possible is already 153 characters long. So instead of finding superpermutations by trial and error, mathematicians wanted to find a general rule: a formula they could use to find the minimum length of a superpermutation of any number of elements.

Back in 1993, a couple of mathematicians thought they’d done just that, but their conjecture was shown to be false for sets with more than five elements in 2014, and the problem was reopened. Then last week, mathematician Robin Houston stumbled upon the anonymous proof on the Haruhi message board – and excited researchers gathered online for an impromptu peer review.

A curious situation. The best known lower bound for the minimal length of superpermutations was proved by an anonymous user of a wiki mainly devoted to anime. https://t.co/z3wVAcUJl1

— Robin Houston (@robinhouston) October 23, 2018 The verdict? The proof checks out, and “Anonymous 4chan Poster” is now a listed co-author on a new combinatorics paper presenting the result.

And thanks to a recent proof showing an upper bound to the problem, it looks like this 25-year-old math problem may be on track to be solved once and for all.

“It might be possible to crack the thing completely open,” Houston told The Verge.

So should we expect the anonymous 4channer to come forward? Possibly not any time soon – according to their proof, they still have nearly 4.3 million years' worth of Haruhi left to watch before they have time to enjoy their new mathematical fame.

TOPICS: Education; Science
KEYWORDS: 4chan; anime; math; science; stringtheory
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A lower bound on the length of the shortest superpattern

anonymous 4channer

listed on paper as: Anonymous 4chan Poster, Robin Houston, Jay Pantone, and Vince Vatter

1 posted on 10/30/2018 6:55:18 PM PDT by Eddie01

To: Eddie01
2 posted on 10/30/2018 6:59:52 PM PDT by Eddie01

To: Eddie01

The power of weaponized autism.

3 posted on 10/30/2018 7:00:02 PM PDT by wastoute (Government cannot redistribute wealth. Government can only redistribute poverty.)

To: Eddie01

“You may not have heard of The Melancholy of Haruhi Suzumiya”

****

Yes, I (unfortunately) do LOL. And that’s why I joined 4Chan in the first place before it became infamous for Trumpers and they have a hilarious forum on manga and anime..without the ahole Naruto and One Piece fans which infest other manga forums. Plus, I have “dealings” with Funimation..:)

4 posted on 10/30/2018 7:00:43 PM PDT by max americana (Fired libtard employees 9 consecutive times at every election since 08'. I hope all liberals die.)

To: wastoute

Gotta go to K=Mart

5 posted on 10/30/2018 7:01:10 PM PDT by Eddie01

To: Eddie01

16 trucks

6 posted on 10/30/2018 7:01:34 PM PDT by blueunicorn6 ("A crack shot and a good dancer")

To: Eddie01
#1: "listed on paper as: Anonymous 4chan Poster, Robin Houston, Jay Pantone, and Vince Vatter "

"Trust The Plan."

7 posted on 10/30/2018 7:03:42 PM PDT by Governor Dinwiddie (Nuke the Caravan!)

To: Eddie01

4chan.

This gets even stranger. The Haruhi supermutation genius and Qanon?

They are the same person.

I gotta start hanging out on the dark side of the Internet more.

8 posted on 10/30/2018 7:06:00 PM PDT by Responsibility2nd

To: Eddie01

Is there a youtube video of this I might understand?

9 posted on 10/30/2018 7:06:08 PM PDT by SMGFan ( .)

To: Eddie01

Bookmark...

10 posted on 10/30/2018 7:07:43 PM PDT by SunTzuWu

To: wastoute
This whole original post was nothing without your cogent succinct summation. I suspect you might be the 4Chan Anonymous poster.
11 posted on 10/30/2018 7:10:31 PM PDT by higgmeister ( In the Shadow of The Big Chicken)

To: Eddie01
Did anyone solve Korman's enigma yet?
12 posted on 10/30/2018 7:10:41 PM PDT by Mark17 (Genesis chapter 1 verse 1. In the beginning GOD....And the rest, as they say, is HIS-story)

To: Responsibility2nd

4chan.

This gets even stranger. The Haruhi supermutation genius and Qanon?

They are the same person.

I gotta start hanging out on the dark side of the Internet more.
*****************************************
The time-traveling future US President Baron Trump.

13 posted on 10/30/2018 7:12:18 PM PDT by House Atreides (BOYCOTT the NFL, its products and players 100% - PERMANENTL)

To: Eddie01
All this attention for a cartoon?

What are the possible sequences for watching the Stones?

*Fred & Barney.

14 posted on 10/30/2018 7:12:22 PM PDT by Deaf Smith (When a Texan takes his chances, chances will be taken that's fore sure)

To: SMGFan

I don’t know,
Didn’t understand the problem.

15 posted on 10/30/2018 7:13:29 PM PDT by Big Red Badger (Despised by the Despicable!)

To: Deaf Smith
Where n = number of Stone's videos Every superpermutation for the set of permutations of length n has length at least = n! + (n − 1)! + (n − 2)! + n − 3. There you go.
16 posted on 10/30/2018 7:17:34 PM PDT by Eddie01

To: Eddie01
Where n = number of Stone's videos

Every superpermutation for the set of permutations of length n has length at least = n! + (n - 1)! + (n - 2)! + n - 3.

There you go.

17 posted on 10/30/2018 7:19:44 PM PDT by Eddie01

To: Deaf Smith

Some anime is far better written and more involving than anything Hollywood can come up with.

Personally, I have no use for mathematics in my life (a life-long habit after failing Trig in High School), but I do own several copies of “The Melancholy of Haruhi Suzumiya” (and the sequels) and find the complicated time travel plot quite mind-blowing (that said, I didn’t enjoy watching it out of order when I first saw it years ago, and I’m glad they finally put the episodes in chronological order).

Think of it this way. The best Japanese anime is to “The Flintstones” as Beethoven is to rap music.

18 posted on 10/30/2018 7:20:42 PM PDT by Pravious

To: Eddie01

Wow, amazing. Great story - thanks for posting it.

I’ve never heard of a “superpermutation” before, but the article did a good job explaining it. Turns out I’ve been evaluating them in my head when I play backgammon...as well as mentally calculating odds for the various permutations. I still can’t get my BG ranking up to 1,700, though.

19 posted on 10/30/2018 7:36:53 PM PDT by ProtectOurFreedom

To: Eddie01

Given the entire set of possible human actions or statements, find all the permutations that result in a leftist/globalist calling a conservative racist. Bzzzt, time’s up. It is a trick question, any/all combinations and permutations done, said, or even considered by a conservative will be labeled as racist. Meanwhile Clinton can let slip an incredibly crass comment (revealing how she really feels) and get a complete pass...

20 posted on 10/30/2018 7:48:10 PM PDT by ThunderSleeps ( Be ready!)