B3I1P3Y4R1A1M3I1D2
19 points
BIPYRAMID is validvalid
a polyhedron consisting of a pyramid joined at its base to its mirror image [n BIPYRAMIDS]
a crystal formed of two pyramids base to base [n -S]
a polyhedron consisting of a pyramid joined at its base to its mirror image [n BIPYRAMIDS]
a crystal formed of two pyramids base to base [n -S]