the carrier of T c= Funcs I,the carrier of S
by A1, YELLOW_1:28;
then A2:
Funcs the carrier of N,the carrier of T c= Funcs the carrier of N,(Funcs I,the carrier of S)
by FUNCT_5:63;
A3:
the mapping of N in Funcs the carrier of N,the carrier of T
by FUNCT_2:11;
then A4:
rng ((commute the mapping of N) . i) c= the carrier of S
by A2, EQUATION:3;
dom ((commute the mapping of N) . i) = the carrier of N
by A3, A2, EQUATION:3;
then reconsider f = (commute the mapping of N) . i as Function of the carrier of N,the carrier of S by A4, FUNCT_2:def 1, RELSET_1:11;
set A = NetStr(# the carrier of N,the InternalRel of N,f #);
A5:
RelStr(# the carrier of NetStr(# the carrier of N,the InternalRel of N,f #),the InternalRel of NetStr(# the carrier of N,the InternalRel of N,f #) #) = RelStr(# the carrier of N,the InternalRel of N #)
;
[#] N is directed
by WAYBEL_0:def 6;
then
[#] NetStr(# the carrier of N,the InternalRel of N,f #) is directed
by A5, WAYBEL_0:3;
then reconsider A = NetStr(# the carrier of N,the InternalRel of N,f #) as strict net of S by A5, WAYBEL_0:def 6, WAYBEL_8:13;
take
A
; ( RelStr(# the carrier of A,the InternalRel of A #) = RelStr(# the carrier of N,the InternalRel of N #) & the mapping of A = (commute the mapping of N) . i )
thus
( RelStr(# the carrier of A,the InternalRel of A #) = RelStr(# the carrier of N,the InternalRel of N #) & the mapping of A = (commute the mapping of N) . i )
; verum