Number of massive binaries in each 10k-* model in time (averaged over each model’s realisations). The models are separated by their initial r_h (columns), primordial binary systems (rows), and their semi-major axes (colours). In each plot, the top horizontal axis shows the evolutionary time in the initial half-mass relaxation times, and the lower horizontal axis is in multiples of τ_rh at the end of the simulation (to mimic the ‘present-day’ value). While we permit the dynamical formation of the low-mass (m₃+m₃) or mixed (m_1,2+m₃) binaries in the simulations, the numbers here only show the massive (m₁+m₂) binaries, including component switching. However, if the primordial binary goes through a state of an unstable triple, it is not counted towards N_bin (which is why we sometimes see the number of binaries decreasing and then increasing again).