let G3, G4 be _Graph; for V being set
for G1 being addLoops of G3,V
for G2 being addLoops of G4,V st G3 == G4 holds
G2 is G1 -Disomorphic
let V be set ; for G1 being addLoops of G3,V
for G2 being addLoops of G4,V st G3 == G4 holds
G2 is G1 -Disomorphic
let G1 be addLoops of G3,V; for G2 being addLoops of G4,V st G3 == G4 holds
G2 is G1 -Disomorphic
let G2 be addLoops of G4,V; ( G3 == G4 implies G2 is G1 -Disomorphic )
assume A1:
G3 == G4
; G2 is G1 -Disomorphic
per cases
( V c= the_Vertices_of G3 or not V c= the_Vertices_of G3 )
;
suppose A2:
V c= the_Vertices_of G3
;
G2 is G1 -Disomorphic consider F0 being
PGraphMapping of
G3,
G4 such that A3:
(
F0 = id G3 &
F0 is
Disomorphism )
by A1, GLIBPRE0:75;
A4:
(F0 _V) | V is
one-to-one
by A3, FUNCT_1:52;
A5:
dom ((F0 _V) | V) =
(dom (F0 _V)) /\ V
by RELAT_1:61
.=
V
by A2, A3, XBOOLE_1:28
;
A6:
rng ((F0 _V) | V) =
((id G3) _V) .: V
by A3, RELAT_1:115
.=
V
by A2, FUNCT_1:92
;
consider F being
PGraphMapping of
G1,
G2 such that
(
F _V = F0 _V &
(F _E) | (dom (F0 _E)) = F0 _E )
and
( not
F0 is
empty implies not
F is
empty )
and
(
F0 is
total implies
F is
total )
and
(
F0 is
onto implies
F is
onto )
and
(
F0 is
one-to-one implies
F is
one-to-one )
and
(
F0 is
directed implies
F is
directed )
and
(
F0 is
weak_SG-embedding implies
F is
weak_SG-embedding )
and
(
F0 is
isomorphism implies
F is
isomorphism )
and A7:
(
F0 is
Disomorphism implies
F is
Disomorphism )
by A2, A4, A5, A6, Th29;
thus
G2 is
G1 -Disomorphic
by A3, A7, GLIB_010:def 24;
verum end; end;