Bidiminished rectified pentachoron

The bidiminished rectified pentachoron, antiduowedge, square-tetrahedral wedge, or bidrap, is a CRF segmentochoron (designated K-4.8 on Richard Klitzing's list). It consists of 1 tetrahedron, 2 triangular prisms, and 4 square pyramids.

It can be viewed as a segmentochoron between a square and a tetrahedron, between a triangle and a square pyramid, or between a triangular prism and a perpendicular line.

It can also be viewed as a wedge of the rectified pentachoron, formed by removing two non-adjacent vertices by cutting off triangular prismatic pyramids. As a result one octahedron cell gets cut down to an equatorial square only, while the other 4 get diminished down to square pyramids.

Vertex coordinates
The vertices of a bidiminished rectified pentachoron of edge length 1 are given by:


 * (+1/2, 0, –$\sqrt{2}$/4, 0)
 * (0, ±1/2, $\sqrt{2}$/4, 0)
 * (±1/2, ±1/2, 0, $\sqrt{15}$/4)