Christopher Danielson has gotten making spiraling polygons in real life (cf. spiraling pentagons ) and that got me playing with virtual ones again. In particular, nice closed formations. (Try 2 sets of 7 nonagons for example.) The sketch is a bit hinky, and right now I have this odd sketch and a separate even one. The heptagrin was a name suggested by Matt Parker, that I saw in this post from Jess Hawke, Heptagrin Girl, via Kathryn Peake, https://www.geogebra.org/kathrynp. These are fun; beware of rabbit holes.