reserve l, m, n for Nat,
  i,j,k for Instruction of SCMPDS,
  I,J,K for Program of SCMPDS,
  p,q,r for PartState of SCMPDS;
reserve a,b,c for Int_position,
  s,s1,s2 for State of SCMPDS,
  k1,k2 for Integer;
reserve x for set;
reserve l,l1,loc for Nat;

theorem
  not a in dom Start-At(l,SCMPDS)
proof
A1: dom Start-At(l,SCMPDS) = {IC SCMPDS} by FUNCOP_1:13;
  assume
  a in dom Start-At(l,SCMPDS);
  then a = IC SCMPDS by A1,TARSKI:def 1;
  hence contradiction by SCMPDS_2:43;
end;
