14-4 step prism

The 14-4 step prism is a convex isogonal polychoron and a member of the step prism family. It has 7 rhombic disphenoids and 42 phyllic disphenoids of three kinds as cells, with 14 (2 rhombic and 12 phyllic disphenoids) joining at each vertex.

Vertex coordinates
Coordinates for the vertices of a 14-4 step prism inscribed in a tetradecagonal duoprism with base lengths a and b are given by: where k is an integer from 0 to 13. If the edge length differences are to be minimized, the ratio of a:b must be equivalent to 1:$$\sqrt{\frac{1+\cos\frac{2\pi}{7}}{1+\cos\frac\pi7}}$$ ≈ 1:0.92414.
 * (a*sin(πk/7), a*cos(πk/7), b*sin(3πk/7), b*cos(3πk/7)),