Octahedral cupola

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Octahedral cupola is a four-dimensional figure formed by an octahedron and a parallel rhombicuboctahedron. They are connected by 20 triangular prisms and 6 square pyramids. It can be formed by slicing a larger 4D shape called the runcinated 24-cell with a plane that runs parallel to an octahedral cell. In standard projections of the runcinated 24-cell, the octahedral cupola can be seen.