Group Graph Definition/Meaning:
A directed graph that represents a finite
group G; the vertices of
the graph represent elements of the group and the edges represent
the group. If edge E (representing generator g) joins vertices V and V
(representing group elements v and v' respectively) then
v ο g = v'
where ο is the group operation. Each vertex of the group graph will have outdegree (see degree) equal to the number of generators of the group.