let C, D be Category; for F being Functor of C,D
for I being Indexing of D
for T being TargetCat of I
for E being Categorial Category
for G being Functor of T,E holds (G * I) * F = G * (I * F)
let F be Functor of C,D; for I being Indexing of D
for T being TargetCat of I
for E being Categorial Category
for G being Functor of T,E holds (G * I) * F = G * (I * F)
let I be Indexing of D; for T being TargetCat of I
for E being Categorial Category
for G being Functor of T,E holds (G * I) * F = G * (I * F)
let T be TargetCat of I; for E being Categorial Category
for G being Functor of T,E holds (G * I) * F = G * (I * F)
reconsider T9 = T as TargetCat of I * F by Th24;
let E be Categorial Category; for G being Functor of T,E holds (G * I) * F = G * (I * F)
let G be Functor of T,E; (G * I) * F = G * (I * F)
reconsider G9 = G as Functor of T9,E ;
reconsider GI = rng (G * I) as TargetCat of (G * (I -functor (D,T))) -indexing_of D by Def17;
A1:
I * F = ((I -functor (D,T)) * F) -indexing_of C
by Th23;
A2:
((G * (I -functor (D,T))) -indexing_of D) -functor (D,GI) = G * (I -functor (D,T))
by Th18;
( G * I = (G * (I -functor (D,T))) -indexing_of D & Image F is Subcategory of D )
by Def17;
hence (G * I) * F =
((((G * (I -functor (D,T))) -indexing_of D) -functor (D,GI)) * F) -indexing_of C
by Def16
.=
((G * (I -functor (D,T))) * F) -indexing_of C
by A2, Th2
.=
(G * ((I -functor (D,T)) * F)) -indexing_of C
by RELAT_1:36
.=
(G9 * ((I * F) -functor (C,T9))) -indexing_of C
by A1, Th18
.=
G * (I * F)
by Def17
;
verum