Icosahedron
Icosahedron[] represents a regular icosahedron centered at the origin with unit edge length.
Icosahedron[l] represents an icosahedron with edge length l.
Icosahedron[{θ,ϕ},…] represents an icosahedron rotated by an angle θ with respect to the z axis and angle ϕ with respect to the y axis.
Icosahedron[{x,y,z},…] represents an icosahedron centered at {x,y,z}.
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