Primordial blackholes and gravitational waves for an inflection-point
  model of inflation
  In this article we provide a new closed relationship between cosmic abundance
of primordial gravitational waves and primordial blackholes originated from
initial inflationary perturbations for inflection-point models of inflation
where inflation occurs below the Planck scale. The current Planck constraint on
tensor-to-scalar ratio, running of the spectral tilt, and from the abundance of
dark matter content in the universe, we can deduce a strict bound on the
current abundance of primordial blackholes to be within a range, $9.99712\times
10^{-3}<\Omega_{PBH}h^{2}<9.99736\times 10^{-3}$.
