Assertion: octahedron's edge | /r/CapableOf | represent the angle π/n
Facets:
value: between the mirrors
type: LOCATION
Source sentences:
text: The graph represents Coxeter group I 2 (n), with each node representing a mirror, and the edge representing the angle π/n between the mirrors, and a circle is given around one or both mirrors to show which ones are active.