Concerning "Mariam" Al-Asturlabiya ( A warning about how romanticizing past figures (in this case the only woman astrolabist known from the medieval Islamic world; see also can result in creating biographical details for them out of thin air.

Interactive 3d knot table:

One of many interesting visualizations on "the little grasshopper",, by Philip Rideout (author of the svg3d Python library that I linked earlier)

Going to start my Mastodon account with a result I put quite a bit of work into: Sorting 11 inputs using a sorting network requires 35 comparisons and sorting 12 inputs requires 39 comparisons. I still haven't finished writing the paper (and should be working on that instead), but all the code including a formal proof in Isabelle/HOL is on github:

Kowhaiwhai are repeating decorative patterns used in New Zealand on Maori buildings. The National Library of NZ has a number of good examples at and there's a brief guide to their interpretation at

I can't find much analysis of their structure, though, beyond pointing to frieze groups for their symmetries. The part that interests me more is their fractal-like swooping structure, reminiscent of (and in some cases directly modeled on) fern fronds.

I have a user interface problem that I hope isn't only solved by adding yet another option for authors to understand.

Student types a mathematical expression. We allow implicit multiplication, so `xy` is interpreted as `x*y`.
What to do about `pi`? Is it `p*i` or `π`?

I guess most of the time, you'd expect it to be interpreted as π. But you might be doing something with complex numbers, and `p*i` is really what you meant.
I suppose rendering π would at least give you a hint to add the * symbol

I have made a version of Minesweeper where if you're forced to guess you'll always be safe — but if you guess when you didn't have to you'll always hit a mine. now has a live preview and completion of LaTeX!
This has been on my to-do list for a long time. You no longer need to worry if LaTeX will display properly or not.


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