def METHOD_NAME(self, series_ring, base_ring):
    r"""
    The cycle index series for the species of sets is given by
    `exp\( \sum_{n=1}{\infty} = \frac{x_n}{n} \)`.
    EXAMPLES::
        sage: S = species.SetSpecies()
        sage: g = S.cycle_index_series()
        sage: g[0:5]
        [p[],
         p[1],
         1/2*p[1, 1] + 1/2*p[2],
         1/6*p[1, 1, 1] + 1/2*p[2, 1] + 1/3*p[3],
         1/24*p[1, 1, 1, 1] + 1/4*p[2, 1, 1] + 1/8*p[2, 2] + 1/3*p[3, 1] + 1/4*p[4]]
    """
    from .generating_series import ExponentialCycleIndexSeries
    res = ExponentialCycleIndexSeries(base_ring)
    if self.is_weighted():
        res *= self._weight
    return res