theorem Th38:
for
G2 being
_Graph for
v being
object for
V being
set for
G1 being
addAdjVertexToAll of
G2,
v,
V st
V c= the_Vertices_of G2 & not
v in the_Vertices_of G2 holds
for
e1,
u being
object holds
( not
e1 DJoins u,
v,
G1 & ( not
u in V implies not
e1 DJoins v,
u,
G1 ) & ( for
e2 being
object st
e1 DJoins v,
u,
G1 &
e2 DJoins v,
u,
G1 holds
e1 = e2 ) )