Enneagonal prism
| Enneagonal prism | |
|---|---|
 | |
| Type | Uniform polyhedron |
| Faces |
2 Enneagons 9 squares |
| Edges | 27 |
| Vertices | 18 |
| Vertex configuration | 9.4.4 |
| Wythoff symbol | 2 9 | 2 |
| Coxeter diagram |
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| Symmetry group | D9h, [9,2], (*922), order 36 |
| Rotation group | D9, [9,2]+, (922), order 18 |
| Dual polyhedron | Enneagonal dipyramid |
| Properties | convex semiregular |
| Vertex figure | |
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In geometry, the enneagonal prism (or nonagonal prism) is the seventh in an infinite set of prisms, formed by square sides and two regular enneagon caps.
If faces are all regular, it is a semiregular polyhedron.
Related polyhedra
| Symmetry | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
|---|---|---|---|---|---|---|---|---|---|---|
| [2n,2] [n,2] [2n,2+] |
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