Triangular pyramidal symmetry

Triangular pyramidal symmetry, also known as trippyric symmetry and notated as A2×I, is a 3D spherical symmetry group. It is the symmetry group of the triangular pyramid and occurs as a subgroup in all of tetrahedral, octahedral, and icosahedral symmetry.

Subgroups

 * A2+×I (maximal)
 * A1×I×I (maximal)
 * I×I×I