Viability of Arctan Model of f(R) Gravity for Late-time Cosmology
  $f(R)$ modifications of Einstein's gravity is an interesting possibility to
explain the late time acceleration of the Universe. In this work we explore the
cosmological viability of one such $f(R)$ modification proposed in
(Kruglov:2013). We show that the model violates fifth-force constraints. The
model is also plagued with the issue of curvature singularity in a spherically
collapsing object, where the effective scalar field reaches to the point of
diverging scalar curvature.
