reserve m,n for Nat,
  a,b for Int_position,
  i,j for Instruction of SCMPDS,
  s,s1,s2 for State of SCMPDS,
  I,J for Program of SCMPDS;

theorem Th1:
  for n1,n2 be Nat holds DataLoc(n1,n2) = intpos(n1+n2)
proof
  let n1,n2 be Nat;
  thus DataLoc(n1,n2)=[1,|.n1+n2.|] by SCMPDS_2:def 3
    .=[1,n1+n2] by ABSVALUE:def 1
    .=intpos(n1+n2);
end;
