Type IIP Supernova Progenitors III: Blue to Red Supergiant Ratio in Low
  Metallicity Models with Convective Overshoot
  The distribution of stars in the Hertzsprung Russell diagram (HRD) for a
stellar conglomeration represents a snapshot of its evolving stellar
population. Some of the supergiant stars may transit the HRD from blue to red
and then again to blue during their late evolutionary stages, as exemplified by
the progenitor of SN 1987A. Others may transit a given part of the HRD more
than twice in a "blue loop" and end up as red supergiants before they explode.
Since stars in blue loops spend a considerable part of their lives there, these
stages may change the relative number of modeled supergiants in the HRD. Their
lifetimes in turn depend upon the initial mass of the star, how convection in
its interior is modeled, and how much mass loss takes place during its
evolution. The observed ratio of the number of blue to red supergiants and
yellow to red supergiants sensitively test the stellar evolution theory. We
compare modeled number ratios of these supergiants with observed data from the
Large Magellanic Cloud as it has a metallicity very similar to that of the
environment of SN 2013ej. We successfully model these by taking into account
moderate (exponential) convective overshooting. We explore its effect on the
final radius and mass of the star prior to core collapse. The radius differs
dramatically with overshoot. These factors controlling pre-supernova structure
may affect the post-explosion optical/IR light curves and spectral development.
