In geometry, the decagrammic antiprism is one in an infinite set of nonconvex antiprisms formed by triangle sides and two regular star polygon caps, in this case two decagrams.
| Decagrammic antiprism | |
|---|---|
 | |
| Type | Uniform polyhedron |
| Faces | 2 Decagrams 20 triangles |
| Edges | 40 |
| Vertices | 20 |
| Vertex configuration | 10⁄3.3.3.3 |
| Wythoff symbol | -2 2 10⁄3 |
| Symmetry group | D10d, [2+,20], (2*10), order 40 |
| Dual polyhedron | Decagrammic deltohedron |
| Properties | nonconvex |
| Vertex figure | |
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