Three Pentagrams (from 2011)

I ran into this on Facebook, where I posted it in 2011. That was the year before I started this blog.

An Intermediate Form Between the Icosidodecahedron and the Rhombic Triacontahedron

This polyhedron combines the faces of an icosidodecahedron (red and blue) with the those of a rhombic triacontahedron (green). The gaps between those two sets of polygons are the yellow rectangles. I made this using the “morph duals by expansion” function of Stella 4d: Polyhedron Navigator. You can try this program for yourself, free of charge, at http://www.software3d.com/Stella.php.

Blues and Violets

This was created using Geometer’s Sketchpad and MS-Paint.

At 53, My Age Is a Prime Number Again

It has long been a tradition of mine to make star polygons to mark my birthdays. Since I’m 53 today, here’s a 53-pointed star.

A Tessellation for the New Year MMXXI

Here’s another version, with different colors: