Waldemar Cordeiro
I was captured by the elegance of this art from Waldemar Cordeiro, so I made a sketch where you could play with the pattern. Click the pattern box to see the GeoGebra.
First seen at: http://vjeranski.tumblr.com/post/114237113933/waldemar-cordeiro-untitled-china-ink-and-gouache
What do you notice? What questions can you ask? What math vocabulary do you need to describe it?