Icosahedral pyramid

Icosahedral pyramid

Schlegel diagram
Type Polyhedral pyramid
Schläfli symbol ( ) ∨ {3,5}
Cells 21 1 icosahedron
20 tetrahedra
Faces 50 20+30 {3}
Edges 12+30
Vertices 13
Dual Dodecahedral pyramid
Symmetry group H3, [5,3,1], order 120
Properties convex, regular-faces

In 4-dimensional geometry, the icosahedral pyramid is bounded by one icosahedron on the base and 20 triangular pyramid cells which meet at the apex. Since an icosahedron has a circumradius divided by edge length less than one,[1] the tetrahedral pyramids can made with regular faces.

The regular 600-cell has icosahedral pyramids around every vertex.

The dual to the icosahedral pyramid is a dodecahedral pyramid, seen as an dodecahedral base, and 20 regular pentagonal pyramid meeting at an apex.

References

  1. Richard Klitzing, 3D convex uniform polyhedra, x3o5o - ike, circumradius sqrt[(5+sqrt(5))/8 = 0.951057

External links

Wikimedia Commons has media related to Pyramids (geometry).