Hacker News new | past | comments | ask | show | jobs | submit login
Flexagon (wikipedia.org)
166 points by jerbear4328 10 months ago | hide | past | favorite | 39 comments



Vi Hart had a great vid on Hexaflexagons https://www.youtube.com/watch?v=VIVIegSt81k


I immediately thought of those videos when I read the title, but somehow she is missing from the wiki page, even though there is a section on popular culture.


Cool thing about wiki is that you can edit it! That way the next person to read it gets the benefit of your knowledge.


> Cool thing about wiki is that you can edit it! That way the next person to read it gets the benefit of your knowledge.

Only if they're lucky to arrive in the narrow window between you making your edit and it getting reverted by the power user squatting the page. In practice you can't really edit wikipedia unless you put a lot of time and effort into getting good at wikipedia politics.


This is not true in my experience; you can make a wide range of possible edits without being reverted. Knowing which ones those are requires a good understanding of Wikipedia policy, not its politics. (There is politics, but it's not like every edit is a battle of minds.)

You'd need to read up on the notability guidelines and find a secondary source to figure whether you can make this edit stick. Though then again, there's often no "power user squatting the page" of any kind, so it might not be reverted even if you fail to adhere to this.


There is a link at the very bottom of the External Links section, but yeah, that is strange. Well, Wikipedia is the free encyclopedia anyone can edit.


Thanks Filipecgarcia for updating!

> m including Vi Hart reference [0]

[0]: https://en.wikipedia.org/w/index.php?title=Flexagon&diff=pre...


Is it just me or does that read like GPT


It's all GPT, training the next generation of GPTs so it knows how to produce even more empty words and meaningless fluff.


same


Watch the whole playlist series, including the mexihexaflexagons


I made a tetratetraflexagon for my wedding program. I ended up making a script to use ImageMagick to convert four images into two images suitable for printing on both sides of an 8.5"x11" sheet of paper. The scripts, example images, and instructions are here:

https://www.timpark.org/making-a-tetratetraflexagon/


The recursive card you linked (link broken) is very impressive as well:

https://kellianderson.com/blog/2011/10/11/talks-and-a-recurs...

The concept is one thing but the execution takes it to another level.


I did notice the link was broken, but didn't want to wait until I had time to fix it before commenting. I've fixed it and a couple of other ones. Thanks.


Direct video link: https://vimeo.com/30392799


Thanks for the instructions. I'm going to borrow them but I'll credit you as my source (linking to the webpage.)



I have never been less enlightened by a wikipedia page. Some youtube videos cleared up at least the mechanics of the basic versions, but what it means to have the various higher order flexagons is completely mysterious to me even having read this page.


If you want the more realistic introduction that introduced me to hexaflexagons, Vihart's YouTube videos are excellent: https://youtu.be/VIVIegSt81k


Are these different from the paper things kids made in middle school?


I think so, as the other reply points out.

And I want to encourage everyone to try their hand at making one of these. They're deceptively more interesting than they would appear to be at first glance.

And plus-one on the recommendations for Vi Hart's videos on Hexaflexagons also mentioned here.



Oh man! I remembered some of the most vulgar iterations of this artifact back in primary...


Here's a good example: https://youtube.com/watch?v=oqQwWRalcA0

It's different than a "cootie catcher."


Oh that is very different but very cool, thanks.


The glue-free cyclic hexatetraflexagon is my favorite. IMO it's actually really easy to make; I'm not sure why the article calls it complicated.


I didn't know this is what they were called. I have a desk toy called a shashibo that I think is based on this. Fun and pretty sturdy little thing.



Vihart’s videos are excellent. I’ve watched her introductory video on hexaflexagons maybe 20 times: https://youtu.be/VIVIegSt81k?si=t_qrkiqUTTfy2l4d


Her videos, the last 2 external links on Wikipedia, are excellent introductions indeed. She even recreates the history of how they originated

> The discovery of the first flexagon, a trihexaflexagon, is credited to the British mathematician Arthur H. Stone, while a student at Princeton University in the United States in 1939. His new American paper would not fit in his English binder so he cut off the ends of the paper and began folding them into different shapes.


Her video is an animation of a Martin Gardner "Mathematical Games" article that kicked off the craze. It's been published in a few of his books of article collections.

https://www.google.com/search?q=Martin%20Gardner%20%22Mathem...


Indeed; the story of its origins may also be found at the start of chapter 1 of Gardner's "Hexaflexagons and other mathematical diversions" book [1].

[1] http://geofhagopian.net/papers/GARDNER01.pdf


Being from El Paso, I'd argue for calling this a Tex-Mexiflexagon :)

Looks delicious! I'm looking forward to trying this sometime.


Before clicking I thought it was about flexhedra, but I got confused. But since there is seemingly no Wikipedia page for it here is a French video (subtitled, hopefully with a high enough quality) describing it briefly. https://www.youtube.com/watch?v=Kg3_gLO-reE


My 7th grade science teacher (hi Mrs. Ericson!) had us make tetratetraflexagons in 1998 and I thought, literally until today, that she had made up that word. She also has us make science-themed dodecahedrons so I guess I should have been clued into the fact that she secretly loved geometry / topology.


i remember fiddling with these in the late 1960s after reading about them in one of martin gardner's books. quite a lot of fun for basically no cost.


See also "kaleiodocycles" (the book to build some with Escher tilings is one of the fondest memories of my childhood)


I can not recommend this enough, a must have if you like Escher's Art and are in weird geometric stuff.

https://www.amazon.de/M-C-Escher-Kaleidozyklen-Taschen-speci...


Hexagon is the bestagon




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: