13-5 step prism

The 13-5 step prism is a convex isogonal polychoron, member of the step prism family. It has 13 tetragonal disphenoids and 26 phyllic disphenoids as cells. It is also the pentagonal funk tegum.

Vertex coordinates
Coordinates for the vertices of a 13-5 step prism inscribed in a unit-edged tridecagonal duoprism are given by: where k is an integer from 0 to 12.
 * (sin(2πk/13), cos(2πk/13), sin(10πk/13), cos(10πk/13)),

Isogonal derivatives
Substitution by vertices of these following elements will produce these convex isogonal polychora:
 * Tetragonal disphenoid (13): 13-5 step prism
 * Phyllic disphenoid (26): 13-5 double step prism
 * Isosceles triangle (26): 13-5 double step prism
 * Edge (26): 13-5 double step prism