Vertices: | 14 (14[4]) |
Faces: | 16 (14 equilateral triangles + 2 regular 7/3 heptagrams) |
Edges: | 28 |
Symmetry: | 7-fold Antiprismatic (D7v) |
Heptagram-Triangle Angle: | acos(−sqrt(root[189*(x^3)−315*(x^2)+63*x−1])) = acos(−cot(2*π/7)/sqrt(3)) | ≈117.4143079054 degrees |
Triangle-Triangle Angle: | acos(root[27*(x^3)−9*(x^2)−27*x+1]) = acos((1−4*sin(π/14))/3) | ≈87.900284033 degrees |
Dual Solid: | Heptagrammic 7/3 Trapezohedron |
(values below based on edge length = 1) |
Circumscribed Radius: | sqrt(root[64*(x^3)−144*(x^2)+80*x−13]) = sqrt(tan(2*π/7)*tan(2*π/7)+5)/4 | ≈0.64091811725597805808 |
Midscribed Radius: | root[8*(x^3)+8*(x^2)−2*x−1] = cos(π/7)−1/2 | ≈0.40096886790241912624 |
Heptagram Center Radius: | sqrt(root[448*(x^3)−112*(x^2)+1]) = sqrt(3−cot(2*π/7)*cot(2*π/7))/4 | ≈0.38438556440965090093 |
Triangle Center Radius: | sqrt(root[1728*(x^3)−2160*(x^2)+144*x+1]) = sqrt((3*tan(2*π/7)*tan(2*π/7)−1)/48) | ≈0.27828528472345480038 |