let n, loc be Element of NAT ; for I being Program of SCMPDS st loc in dom I holds
(Shift (stop I),n) . (loc + n) = (Shift I,n) . (loc + n)
let I be Program of SCMPDS ; ( loc in dom I implies (Shift (stop I),n) . (loc + n) = (Shift I,n) . (loc + n) )
A1:
dom I c= dom (stop I)
by SCMPDS_4:39;
reconsider l = loc as Element of NAT ;
assume A2:
loc in dom I
; (Shift (stop I),n) . (loc + n) = (Shift I,n) . (loc + n)
hence (Shift I,n) . (loc + n) =
I . l
by VALUED_1:def 12
.=
(stop I) . l
by A2, SCMPDS_4:37
.=
(Shift (stop I),n) . (loc + n)
by A2, A1, VALUED_1:def 12
;
verum