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Twin prime by Ciro Santilli 35 Updated 2025-02-26 +Created 1970-01-01
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Mathieu group by Ciro Santilli 35 Updated 2025-02-26 +Created 1970-01-01
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Contains the first sporadic groups discovered by far: 11 and 12 in 1861, and 22, 23 and 24 in 1973. And therefore presumably the simplest! The next sporadic ones discovered were the Janko groups, only in 1965!
Each is a permutation group on elements. There isn't an obvious algorithmic relationship between and the actual group.
TODO initial motivation? Why did Mathieu care about k-transitive groups?
Their; k-transitive group properties seem to be the main characterization, according to Wikipedia:
  • 22 is 3-transitive but not 4-transitive.
  • four of them (11, 12, 23 and 24) are the only sporadic 4-transitive groups as per the classification of 4-transitive groups (no known simpler proof as of 2021), which sounds like a reasonable characterization. Note that 12 and 25 are also 5 transitive.
Looking at the classification of k-transitive groups we see that the Mathieu groups are the only families of 4 and 5 transitive groups other than symmetric groups and alternating groups. 3-transitive is not as nice, so let's just say it is the stabilizer of and be done with it.
Video 1.
Mathieu group section of Why Do Sporadic Groups Exist? by Another Roof (2023)
Source. Only discusses Mathieu group but is very good at that.
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Selected screenshots by Ciro Santilli 35 Updated 2025-02-26 +Created 1970-01-01
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Figure 1.
2010 Wayback Machine archive of starwarsweb.net
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The Star Wars one. Clearly branded websites like this are rare, which makes finding them all the much more fun. The Reuters article had two of them (Carson and rastadirect.net), so these were probably manually selected from the full hit dataset, and did not serve specifically as entry points. Most of the websites are quite boring and forgetful as you'd expect.
The subtitle "Beyond The Unknown" may be a reference to the Unknown Regions in the Star Wars fictional universe.
Figure 2.
2011 Wayback Machine archive of iranfootballsource.com
. The third Iranian football on top of the two other published by Reuters: iraniangoalkicks.com and iraniangoals.com! Admittedly, this one is the most generic and less well designed one. But still. They pushed the theme too far!
Figure 3.
2010 Wayback Machine archive of dedrickonline.com
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The German one.
The CIA has had a few Germany espionage scandals in the 2010s:
Figure 4.
2010 Wayback Machine archive of lesummumdelafinance.com
. A French one. Because it mentions VTT (Mountain Biking in French), it must focus France.
Figure 5.
2011 Wayback Machine archive of attivitaestremi.com
. An Italian one about extreme sports.
Figure 6.
2010 Wayback Machine archive of noticiasmusica.net
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The Brazilian one.
Figure 7.
2011 Wayback Machine archive of economicnewsbuzz.com
. The Korean one. Love the kawaii style!
Figure 8.
2011 Wayback Machine archive of snapnewsfront.net
. The Japanese one.
Figure 9.
2010 Wayback Machine archive of philippinenewsonline.net
. The Philippine one one.
Figure 10.
2011 Wayback Machine archive of feedsdemexicoyelmundo.com
. The Mexican one.
Figure 11.
2012 Wayback Machine archive of easytraveleurope.com
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Figure 12.
2011 Wayback Machine archive of tee-shot.net
. One of the many golf-themed sites. Golf appears to be quite popular over in Langley. It's exactly what you'd expect for a mid-level spook to do in their free time!
Figure 13.
2011 Wayback Machine archive of nouvellesetdesrapports.com
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Figure 14.
2011 Wayback Machine archive of pangawana.com
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Figure 15.
2011 Wayback Machine archive of recuerdosdeviajeonline.com
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Figure 16.
2011 Wayback Machine archive of theworld-news.net
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Figure 17.
2011 Wayback Machine archive of kessingerssportsnews.com
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Figure 18.
2011 Wayback Machine archive of negativeaperture.com
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Backlinks by Ciro Santilli 35 Updated 2025-02-26 +Created 1970-01-01
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Initial announcements by self on 2023-06-10:
Shared by others soo after:
2023-10-26 twitter.com/cirosantilli/status/1717445686214504830: announcement by self after finding 75 more sites
Second wave:
Some more:
/ny
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Pinned article: ourbigbook/introduction-to-the-ourbigbook-project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Video 1.
Intro to OurBigBook
. Source.
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    Screenshot of the "Derivative" topic page
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    Video 2.
    OurBigBook Web topics demo
    . Source.
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    You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website
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    Figure 3.
    Visual Studio Code extension installation
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    Figure 4.
    Visual Studio Code extension tree navigation
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    Web editor
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    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
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