reserve a,b,k,m,n,s for Nat;
reserve c,c1,c2,c3 for Complex;
reserve i,j,z for Integer;
reserve p for Prime;
reserve x for object;
reserve f,g for complex-valued FinSequence;

theorem Th64:
  <*c1,c2*>" = <*c1",c2"*>
  proof
    <*c1*>" = <*c1"*> & <*c2*>" = <*c2"*> by Th63;
    hence thesis by Th60;
  end;
