Heptagrammic pyramid

{{Infobox polytope The heptagrammic pyramid or shappy is a pyramid with a heptagrammic base and 7 triangles as sides. A version with equilateral triangles exists and is orbiform.
 * type=Segmentotope
 * img= Heptagrammic pyramid.png
 * 3d=
 * off=
 * dim = 3
 * obsa =Shappy
 * faces = 7 triangles, 1 heptagram
 * edges = 7+7
 * vertices = 1+7
 * verf = 1 heptagram, edge length 1
 * verf2 = 7 isosceles triangles, edge lengths 1, 1, 2cos(2π/7)
 * coxeter = ox7/2oo&#x
 * army=Non-RF heppy
 * reg =Shappy
 * symmetry = I{{sub|2}}(7)×I, order 14
 * circum = $$\frac{1}{\sqrt{4-\frac{1}{\sin^2\frac{2\pi}{7}}} ≈ 0.65039$$
 * height = $$\frac{\sqrt{4-\sec^2\frac{3\pi}{14}}}{2} ≈ 0.76877$$
 * volume = $$\frac{7\tan\frac{3\pi}{14}\sqrt{4-\sec^2\frac{3\pi}{14}}}{24} ≈ 0.35763$$
 * dih =
 * dih2 =
 * dual = Heptagrammic pyramid
 * conjugate =Heptagonal pyramid, great heptagrammic pyramid
 * conv=No
 * orientable=Yes
 * nat=Tame}}