for s1, s2 being State of SCMPDS
for n, m being Nat
for i being Instruction of SCMPDS st IC s1 = m & i valid_at m & InsCode i <> 1 & InsCode i <> 3 & (IC s1) + n = IC s2 & DataPart s1 = DataPart s2 holds
( (IC (Exec (i,s1))) + n = IC (Exec (i,s2)) & DataPart (Exec (i,s1)) = DataPart (Exec (i,s2)) )