set t = the State of SCM+FSA;
let l be Element of NAT ; for i being Instruction of SCM+FSA st ( for s being State of SCM+FSA st IC s = l holds
(Exec (i,s)) . (IC ) = succ (IC s) ) holds
NIC (i,l) = {(succ l)}
let i be Instruction of SCM+FSA; ( ( for s being State of SCM+FSA st IC s = l holds
(Exec (i,s)) . (IC ) = succ (IC s) ) implies NIC (i,l) = {(succ l)} )
reconsider I = i as Element of the Object-Kind of SCM+FSA . l by COMPOS_1:def 8;
assume A1:
for s being State of SCM+FSA st IC s = l holds
(Exec (i,s)) . (IC ) = succ (IC s)
; NIC (i,l) = {(succ l)}
reconsider il1 = l as Element of ObjectKind (IC ) by COMPOS_1:def 6;
let x be set ; TARSKI:def 3 ( not x in {(succ l)} or x in NIC (i,l) )
reconsider n = il1 as Element of NAT ;
reconsider p = ((IC ),l) --> (il1,I) as PartState of SCM+FSA by COMPOS_1:37;
reconsider u = the State of SCM+FSA +* p as Element of product the Object-Kind of SCM+FSA by PBOOLE:155;
A3:
u . n = i
by EXTPRO_1:26;
A4:
(ProgramPart u) /. l = u . l
by COMPOS_1:38;
assume
x in {(succ l)}
; x in NIC (i,l)
then A5:
x = succ l
by TARSKI:def 1;
A6:
IC u = n
by EXTPRO_1:26;
then
IC (Following ((ProgramPart u),u)) = succ l
by A1, A3, A4;
hence
x in NIC (i,l)
by A5, A6, A3, A4; verum