Great hendecagram

The great hendecagram, or ghen, is a polygon with 11 sides. It's created by taking the third stellation of a hendecagon. A regular great hendecagram has equal sides and equal angles.

It is one of four stellations of the hendecagon, the other three being the small hendecagram, the hendecagram, and the grand hendecagram.

Vertex coordinates
Coordinates for a heptagon of edge length 2sin(4π/11), centered at the origin, are:


 * (1, 0),
 * (cos(2π/11), ±sin(2π/11)),
 * (cos(4π/11), ±sin(4π/11)),
 * (cos(6π/11), ±sin(6π/11)),
 * (cos(8π/11), ±sin(8π/11)),
 * (cos(10π/11), ±sin(10π/11)).