let m, n be Element of NAT ; for I being preProgram of SCM+FSA holds IncAddr (IncAddr I,m),n = IncAddr I,(m + n)
let I be preProgram of SCM+FSA ; IncAddr (IncAddr I,m),n = IncAddr I,(m + n)
A1:
dom (IncAddr I,m) = dom I
by Def6;
A2:
now let l be
Element of
NAT ;
( l in dom I implies (IncAddr (IncAddr I,m),n) . l = IncAddr (pi I,l),(m + n) )assume A3:
l in dom I
;
(IncAddr (IncAddr I,m),n) . l = IncAddr (pi I,l),(m + n)then pi (IncAddr I,m),
l =
(IncAddr I,m) . l
by A1, AMI_1:def 47
.=
IncAddr (pi I,l),
m
by A3, Th24
;
hence (IncAddr (IncAddr I,m),n) . l =
IncAddr (IncAddr (pi I,l),m),
n
by A1, A3, Th24
.=
IncAddr (pi I,l),
(m + n)
by Th23
;
verum end;
dom (IncAddr (IncAddr I,m),n) = dom (IncAddr I,m)
by Def6;
hence
IncAddr (IncAddr I,m),n = IncAddr I,(m + n)
by A1, A2, Def6; verum