Two spherical stars A and B have densities ρ_A and ρ_B, respectively. They have the same radius, and their masses M_A and M_B satisfy M_B = 2M_A. Star A loses mass such that its radius halves while ρ_A remains constant. The lost mass forms a spherical shell around B with density ρ_A. If v_A and v_B are the escape velocities after this process, and (v_B/v_A) = √(10n/15^(1/3)), find n.