IBM System/360 Updated 2025-07-16
This is a family of computers. It was a big success. It appears that this was a big unification project of previous architectures. And it also gave software portability guarantees with future systems, since writing software was starting to become as expensive as the hardware itself.
Tinker Tailor Soldier Spy (film) Updated 2025-07-16
This is not bad, but some divergences to the better BBC miniseries, which presumably sticks more closely to the novel:
  • in the film Jim Prideaux is captured in a cafe in Prague, in the series it's in the woods. It is therefore much more plausible that he would have been shot.
  • in the film Peter Guillam is played by Benedict Cumberbatch, who feels a bit young to be Ricki Tarr's boss. Not impossible, but still.
  • the series is much less chronological, and more flashback based, as new information becomes available. The film is more chronological, which makes it easier to understand, but less interesting at the same time.
  • in the film they shoot the Russian girl Irina in front of Jim, in the series the fact that she was shot is only known through other sources. The film has more eye candy, which weakens it.
  • Toby Esterhase is not threatened in an airfield, only in a safe ;house in London.
Tree traversal Updated 2025-07-16
In principle one could talk about tree traversal of unordered trees as a number of possible traversals without a fixed order. But we won't consider that under this section, only deterministic ordered tree traversals.
Myoglobin Updated 2025-07-16
From Wikipedia:
In humans, myoglobin is only found in the bloodstream after muscle injury.
Topology Updated 2025-07-16
Just by havin the notion of neighbourhood, concepts such as limit and continuity can be defined without the need to specify a precise numerical value to the distance between two points with a metric.
As an example. consider the orthogonal group, which is also naturally a topological space. That group does not usually have a notion of distance defined for it by default. However, we can still talk about certain properties of it, e.g. that the orthogonal group is compact, and that the orthogonal group has two connected components.
ISO SQL TRIGGER syntax Updated 2025-07-16
TODO what is the standard compliant syntax?
SQLite does not support SQL stored procedures at all, so maybe that's why they can't be standard compliant here: stackoverflow.com/questions/3335162/creating-stored-procedure-in-sqlite
SQL:1999 11.38 covers "Trigger definition". The Abstract syntax tree starts with the CREATE TRIGGER and ends in:
<triggered SQL statement> ::=
  <SQL procedure statement>
This is defined at 13.5 "SQL procedure statement", but that is humongous and I'm not sure what it is at all.
Jacquard machine Updated 2025-07-16
Video 1.
A Jacquard loom in action by NationalMuseumsScotland (2016)
Source. The lack of audio is unsettling!
Mordell's theorem Updated 2025-07-16
The number of points may be either finite or infinite. But when infinite, it is still a finitely generated group.
TODO example.
Multilinear form Updated 2025-07-16
See form.
Analogous to a linear form, a multilinear form is a Multilinear map where the image is the underlying field of the vector space, e.g. .
Transcendental number conjecture Updated 2025-07-16
There's a billion simple looking expressions which are not known to be transcendental numbers or not. It's cute simple to state but hard to prove at its best.
Open as of 2020:
Bibliography:
Video 1.
Why π^π^π^π could be an integer by Stand-up Maths (2021)
Source. Sponsored by Jane Street. Shame.

Unlisted articles are being shown, click here to show only listed articles.