Notes. List of parameters selected for our models/N-body computations. OB stands for observation-based models (Sect. 2.2). Slope values γ = 0.2, α = 4.25, and n = 4 (Eq. (6)) are used for all models. The huge initial SMBH masses in excess of 10¹⁰ M_⊙ are motivated at the end of Sect. 2.2 and in Sect. 2.3. While dynamical masses, M_dyn, and effective radii, R_e, of our model galaxies are constrained by representative galaxies, the break-radius, R_b, is taken from the scaling relation in Rusli et al. (2013). SMBH masses during the N-body computations are linearly increased up to ΔM_• over the typical galaxy cluster lifetime of T ≈ 8 Gyr. The ΔM_• values are selected to equally cover (in log-space) the whole parameter range of SMBH growth rates, which are specified in Sect. 2. Model 9 is computed from z = 1 until z = 0.1.