# Compound of two great heptagrams

Compound of two great heptagrams
Rank2
TypeRegular
Notation
Bowers style acronymNisted
Schläfli symbol{14/6}
Elements
Components2 great heptagrams
Edges14
Vertices14
Measures (edge length 1)
Circumradius${\displaystyle {\frac {1}{2\sin \left({\frac {3\pi }{7}}\right)}}\approx 0.51286}$
Inradius${\displaystyle {\frac {1}{2\tan \left({\frac {3\pi }{7}}\right)}}\approx 0.11412}$
Area${\displaystyle {\frac {7}{2\tan {\frac {3\pi }{7}}}}\approx 0.79885}$
Angle${\displaystyle {\frac {\pi }{7}}\approx 25.71429^{\circ }}$
Central density6
Number of external pieces28
Level of complexity2
Related polytopes
ArmyTed, edge length ${\displaystyle \tan {\frac {\pi }{14}}}$
DualCompound of two great heptagrams
ConjugatesCompound of two heptagons, compound of two heptagrams
Abstract & topological properties
Flag count28
Euler characteristic2
OrientableYes
Properties
SymmetryI2(14), order 28
ConvexNo
NatureTame

The spinostellated tetradecagon or nisted is a polygon compound composed of two great heptagrams. As such it has 14 edges and 14 vertices.

It is the fifth stellation of the tetradecagon.

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

## Vertex coordinates

Coordinates for a compound of two great heptagrams of edge length 2sin(3π/7), centered at the origin, are:

• ${\displaystyle \left(\pm 1,\,0\right),}$
• ${\displaystyle \left(\pm \cos {\frac {\pi }{7}},\,\pm \sin {\frac {\pi }{7}}\right),}$
• ${\displaystyle \left(\pm \cos {\frac {2\pi }{7}},\,\pm \sin {\frac {2\pi }{7}}\right),}$
• ${\displaystyle \left(\pm \cos {\frac {3\pi }{7}},\,\pm \sin {\frac {3\pi }{7}}\right).}$