David Richeson: Division by Zero

I have been using OpenSCAD to generate mathematical objects for 3D printing.

I recently designed and made a string art cardioid sculpture, which is now hanging in our mathematics department’s window.

In my “intro-to-proofs” class, I like to have my students work on some induction problems that are not the usual proof of sums and products of integers.

On June 30, 2025, Mark Brittenham and Susan Hermiller uploaded a preprint to the arXiv called “Unknotting number is not additive under connected sum” (and an updated version on September 15, 2025).

I was looking for information about mathematics programs at other liberal arts colleges, so I put together this collection of links.

I’ve been playing around with Magic Eye images lately.

I use LaTeX to type mathematical documents.

I’ve been on a weird kick lately making images using Excel.

The Mandelbrot set is one of the most stunning geometric objects in all of mathematics.

A few days ago, I posted templates showing how to fold a piece of paper so that you can cut out a hat or spectre tile in one cut.