Assertion: tetrahedron's edge | /r/HasProperty | shared by square
Facets:
Source sentences:
text: The dihedral angle is approximately 1.910633 radians (109.471° OEIS: A156546) at edges shared by two hexagons or 2.186276 radians (125.263° OEIS: A195698) at edges shared by a hexagon and a square.