Temporal evolution of the semimajor axis for simulations with initial separation of Δ = 7 r_H as inFig. 2 (top). Final mass distribution for simulations with Δ∕r_H =7 (blue), 9 (orange), and 11 (green) as in Fig. 3 (bottom). In each simulation, we (a) delayed the start time, (b) reduced the initial total mass, (c) changed the index of the initial embryo distribution, (d) and used the disk evolution with lower turbulent viscosity.