The distance between two stars of masses $$3 M_S$$ and $$6 M_S$$ is 9𝑅. Here 𝑅 is the mean distance between the centers of the Earth and the Sun, and $$M_S$$ is the mass of the Sun. The two stars orbit around their common center of mass in circular orbits with period 𝑛𝑇, where 𝑇 is the period of Earth’s revolution around the Sun.
The value of n is ___.