reserve s for set,
  i,j for Nat,
  c,c1,c2,c3 for Complex,
  F,F1,F2 for complex-valued FinSequence,
  R,R1,R2 for i-element complex-valued FinSequence;

theorem
  -<*c*> = <*-c*>
proof
  reconsider s=c as Element of COMPLEX by XCMPLX_0:def 2;
  -<*s*> = <*compcomplex.s*> by FINSEQ_2:35
        .= <*-c*> by BINOP_2:def 1;
  hence thesis;
end;
