| Vertices: | 14 (14[4]) |
| Faces: | 16 (14 equilateral triangles + 2 regular 7/3 heptagrams) |
| Edges: | 28 |
| Symmetry: | 7-fold Prismatic (D7h) |
| Heptagram-Triangle Angle: | acos(root[27*(x^3)−45*(x^2)−3*x+13])
= acos((4*sin(π/14)+1)/3) | ≈50.947818141 degrees |
| Triangle-Triangle Angle: | acos(sqrt(root[27*(x^3)−189*(x^2)+105*x−7]))
= acos(tan(2*π/7)/sqrt(3)) | ≈316.3835916349 degrees |
| Dual Solid: | Heptagrammic Concave Trapezohedron |
| (values below based on edge length = 1) |
| Circumscribed Radius: | sqrt(root[448*(x^3)−560*(x^2)+224*x−29])
= sqrt(cot(2*π/7)*cot(2*π/7)+5)/4 | ≈0.59350462329578707220 |
| Midscribed Radius: | sqrt(root[448*(x^3)−224*(x^2)+28*x−1])
= 1/(4*sin(2*π/7)) | ≈0.31976200192248315144 |
| Heptagram Center Radius: | sqrt(root[64*(x^3)+48*(x^2)−16*x+1])
= sqrt(cos(π/7)*(1−cos(π/7))) | ≈−0.29870381144714635357 |
| Triangle Center Radius: | −sqrt(root[12096*(x^3)−3024*(x^2)+1])
= −sqrt((3*cot(2*π/7)*cot(2*π/7)−1)/48) | ≈0.13752964967649988638 |