reserve i,j,k for Nat;

theorem Th14:
  for K being left_zeroed right_zeroed add-associative
  right_complementable non empty addLoopStr holds the addF of K is
  having_an_inverseOp
proof
  let K be left_zeroed right_zeroed add-associative right_complementable non
  empty addLoopStr;
  comp K is_an_inverseOp_wrt the addF of K by Th13;
  hence thesis by FINSEQOP:def 2;
end;
