Tetrahedron atop triangular cupola

Tetrahedron atop triangular cupola
Rank	4
Type	Segmentotope
Space	Spherical
Notation
Bowers style acronym	Tetatricu
Coxeter diagram	ooxx3oxxo&#xr
Elements
Cells	2 tetrahedra, 6 triangular prisms, 2 triangular cupolax
Faces	2+6+6 triangles, 6+6 squares, 1 hexagon
Edges	6+6+6+12
Vertices	1+6+6
Vertex figures	1 triangular antiprism, edge lengths 1 (base) and √2 (sides)
	6 skewed rectangular pyramids, edge lengths, base edge lengths 1, √2, 1, √2, side edge lengths 1, 1, √2, √2
	6 phyllic disphenoids, edge lengths 1 (2), √2 (3), and √3 (1)
Measures (edge length 1)
Circumradius	1
Hypervolume	$\frac{5\sqrt5}{24} \approx 0.46586$
Dichoral angles	Trip-4-trip: $\arccos\left(-\frac23\right) \approx 131.81031^\circ$
	Tet-3-trip: $\arccos\left(-\frac{\sqrt6}{4}\right) \approx 127.76124^\circ$
	Tricu-6-tricu: $\arccos\left(-\frac14\right) \approx 104.477512^\circ$
	Tet-3-tricu: $\arccos\left(\frac14\right) \approx 75.52249^\circ$
	Trip-4-tricu: $\arccos\left(\frac{\sqrt6}{6}\right) \approx 65.905157^\circ$
	trip-3-tricu: $\arccos\left(\frac{\sqrt6}{4}\right) \approx 52.23876^\circ$
Height	$\frac{\sqrt{10}}{4} \approx 0.79057$
Central density	1
Related polytopes
Army	Tetatricu
Regiment	Tetatricu
Conjugate	None
Abstract & topological properties
Euler characteristic	0
Orientable	Yes
Properties
Symmetry	(G2×A1)/2×I, order 12
Convex	Yes
Nature	Tame

Tetrahedron atop triangular cupola, or tetatricu, is a CRF segmentochoron (designated K-4.24 on Richard Klitzing's list). As the name suggests, it consists of a tetrahedron and a triangular cupola as bases, connected by 1 additional tetrahedron, 1 additional triangular cupola, and 6 triangular prisms.

It can be formed by diminishing a tetrahedron atop cuboctahedron segmentochoron by a triangular cupofastegium, leaving a further triangular cupola behind while removing several tetrahedral and triangular prism cells. Therefore, its vertices are a subset of those of the uniform small prismatodecachoron.

Vertex coordinates

The vertices of a tetrahedron atop triangular cupola segmentochoron of edge length 1 are given by:

• $\pm\left(0,\,0,\,0,\,\pm1\right)$,
• $\pm\left(0,\,0,\,\pm\frac{\sqrt3}{2},\,\pm\frac12\right)$,
• $\left(0,\,-\frac{\sqrt6}{3},\,\frac{\sqrt3}{3},\,0\right)$,
• $\left(0,\,-\frac{\sqrt6}{3},\,-\frac{\sqrt3}{6},\,\pm\frac12\right)$,
• $\left(\frac{\sqrt{10}}{4},\,-\frac{\sqrt6}{4},\,0,\,0\right)$,
• $\left(\frac{\sqrt{10}}{4},\,\frac{\sqrt6}{12},\,-\frac{\sqrt3}{3},\,0\right)$,
• $\left(\frac{\sqrt{10}}{4},\,\frac{\sqrt6}{12},\,\frac{\sqrt3}{6},\,\pm\frac12\right)$.

External links

• Klitzing, Richard. "tetatricu".