mass-luminosity relation this transfers to about 0.25 M$_\odot$.

The total mass of all stars from the PrS amounts to 794 M$_\odot$. We followed the recipes in and used the individual masses to estimate the tidal radius of the Praesepe cluster. In the galactic disk the sphere of influence of a cluster is given by $$x_L = \left(\frac{\rm{G} M_t}{4A(A-B)}\right)^\frac{1}{3} 
  \label{tidal}$$ where $x_L$ is the distance of the Lagrangian points from the centre, $M_t$ is the total mass inside a distance $x_L$ from the centre, G = $4.3 \times 10^{-3} \rm{pc/M_\odot (km/s)^2}$ is the gravitational constant, $A$ and $B$ are Oort’s constants at the position of the Sun. Here we use $A$ (15.3 $\rm{kms}^{-1}\rm{kpc}^{-1}$) and $B$ (-11.9 $\rm{kms}^{-1} \rm{kpc}^{-1}$) from @2017MNRAS.468L..63B. The distance $x_L$ is often referred to as the tidal radius $r_t$ of a cluster. The tidal radius $r_t$ separates, in general, stars gravitationally bound to a cluster from those that are unbound. Adding up the individual masses from the centre outwards we found $r_t$ = 10.77 pc; 725 stars are within $r_t$ and give a tidal mass $M_t$ = 483 M$_\odot$ for Praesepe. Considering our incompleteness at about 0.25 M$_\odot$, this tidal radius is a lower bound. But, even if 