reserve x,y,z for set;
reserve I,J,K for Element of Segm 9,
  i,a,a1,a2 for Nat,
  b,b1,b2,c,c1 for Element of SCM-Data-Loc;

theorem
  for s being SCM-State, t being Element of SCM-Data-Loc, u being
Integer, mk being Element of SCM-Data-Loc st mk <> t holds SCM-Chg(s,t,u).mk =
  s.mk
proof
  let s be SCM-State, t be Element of SCM-Data-Loc, u be Integer, mk be
  Element of SCM-Data-Loc such that
A1: mk <> t;
  not mk in dom(t .--> u) by A1,TARSKI:def 1;
  hence thesis by FUNCT_4:11;
end;
