Nick Sayers obviously loves math – why else would he turn his head into an ode to geometry?
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.
Get that? If you’re interested in doing this yourself, Nick suggests you “use a rhombic paper template starting at the crown, work outwards, and make aesthetic decisions about the 5-, 6-, or 7-way joints depending on local curvature.”