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Pi Day 2022: a regular 30 sided polygon.

Several years ago, I explored approximating Pi with polygons made of Geometiles. I described my findings in this blog. Fast forward to 2022, when Charles Fleischer showed me a polyhedral torus I’ve never seen before, and its boundary was a regular 30-sided polygon. The fancy name for a 30 sided polygon is triacontagon. Triaconta τριάκοντα…
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Introducing Mobies!

This story started with our desire to expand the capability of the Geometiles® to make transformable hinged constructions. In particular, we were interested in making flexagons using the equilateral and square Geometiles tiles. Flexagons are polygons typically made of paper, which can be folded to expose certain faces and hide others. They were invented by…
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Art With a Mathematical Bent at the Japanese Friendship Garden

I recently had the honor of having my mathematical art exhibited in a non-mathematical setting for the first time. The venue was the Japanese Friendship Garden in San Diego, CA, where an exhibit was held for works created during the time of Covid in an effort to heal through art. The title of the exhibit…
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Campanus’ Sphere

In these very uncertain times, I find it comforting to look at something eternal and classical. It’s even better if this is an object whose model I can construct. After months of quarantine, I finally hit upon the perfect pandemic craft object: the Campanus’ Sphere. This beautiful polyhedral frame was frequently portrayed during the Rennaissance…
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