Geometric Haircut
George Hart of Museum of Mathematics takes a look at the new Geometric Haircut that Nick Sayers is sporting.
The obtuse angles of each rhombus meet in groups of three, but the acute angles meet in groups of five, six, or seven, depending on the curvature. In the flatter areas, they meet in groups of six, like equilateral triangles, and in the areas of strong positive curvature they meet in groups of five, but in the negatively curved saddle at the back of the neck, there is a group of seven.