Pentagrammic antiprism

Uniform pentagrammic antiprism
Type	Prismatic uniform polyhedron
Elements	F = 12, E = 20 V = 10 (χ = 2)
Faces by sides	10{3}+2{5/2}
Schläfli symbol	sr{2,5/2}
Wythoff symbol	| 2 2 5/2
Coxeter diagram
Symmetry	D5h, [5,2], (*552), order 20
Rotation group	D5, [5,2]+, (55), order 10
Index references	U79(a)
Dual	Pentagrammic trapezohedron
Properties	nonconvex
Vertex figure 3.3.3.5/2

In geometry, the pentagrammic antiprism is one in an infinite set of nonconvex antiprisms formed by triangle sides and two regular star polygon caps, in this case two pentagrams.

This polyhedron is identified with the indexed name U₇₉ as a uniform polyhedron.

An alternative representation with hollow centers to the pentagrams.

Net

Net (fold the dotted line in the centre in the opposite direction to all the other lines):

See also

• Pentagrammic prism
• Pentagrammic crossed-antiprism

External links

• Weisstein, Eric W. "Pentagrammic antiprism". MathWorld.
• http://www.mathconsult.ch/showroom/unipoly/04.html
• http://www.math.technion.ac.il/~rl/kaleido/data/04.html