- The Early History of Usenet, Part I: Prologue (cs.columbia.edu)
November 2019 is, as best I can recall, the 40th anniversary of the conception of Usenet. (What’s Usenet? The Wikipedia article is ok but not perfect.) I should have written a proper paper; instead, there will (probably) be an irregular series of blog posts. I’ll do Part I of N tonight.
- Sierpiński triangle (Wikipedia)
The Sierpiński triangle, also called the Sierpiński gasket or Sierpiński sieve, is a fractal with the overall shape of an equilateral triangle, subdivided recursively into smaller equilateral triangles. Originally constructed as a curve, this is one of the basic examples of self-similar sets—that is, it is a mathematically generated pattern that is reproducible at any magnification or reduction. It is named after the Polish mathematician Wacław Sierpiński, but appeared as a decorative pattern many centuries before the work of Sierpiński.