 Rank2
TypeRegular
SpaceSpherical
Notation
Schläfli symbol{14/2}
Elements
Components2 heptagons
Edges14
Vertices14
Measures (edge length 1)
Circumradius$\frac{1}{2\sin\frac\pi7} \approx 1.15238$ Inradius$\frac{1}{2\tan\frac\pi7} \approx 1.03826$ Area$\frac{7}{2\tan\frac\pi7} \approx 7.26782$ Angle$\frac{5\pi}{7} \approx 128.57143^\circ$ Central density2
Number of external pieces28
Level of complexity2
Related polytopes
ArmyTed, edge length $\frac{1}{2\cos\frac{\pi}{14}}$ Abstract & topological properties
Flag count28
Euler characteristic2
OrientableYes
Properties
SymmetryI2(14), order 28
ConvexNo
NatureTame

The stellated tetradecagon or stad is a polygon compound composed of two heptagons. As such it has 14 edges and 14 vertices.

As the name suggests, it is the first stellation of the tetradecagon.

Its quotient prismatic equivalent is the heptagonal antiprism, which is three-dimensional.

## Vertex coordinates

Coordinates for a stellated tetradecagon of edge length 2sin(π/7), centered at the origin, are:

• $\left(\pm1,\,0\right),$ • $\left(\pm\cos\frac{\pi}{7},\,\pm\sin\frac{\pi}{7}\right),$ • $\left(\pm\cos\frac{2\pi}{7},\,\pm\sin\frac{2\pi}{7}\right),$ • $\left(\pm\cos\frac{3\pi}{7},\,\pm\sin\frac{3\pi}{7}\right).$ 