reserve i,j,k for Nat;
reserve K for non empty addLoopStr,
  a for Element of K,
  p for FinSequence of the carrier of K,
  R for Element of i-tuples_on the carrier of K;

theorem Th25:
  -(i|->a) = i|->-a
proof
  thus -(i|->a) = i|->((comp K).a) by FINSEQOP:16
    .= i|->-a by VECTSP_1:def 13;
end;
