Equation for $N$-body problem using Jacobi Coordinate

Question

For reference on Jacobi Coordinate used for solving 2-Body problem, I referred Wikipedia Jacobi Coordinate, and on looking at those equation I can't get the meaning of the symbol q in the equation for Vector to center of mass,

R_jk = ( m_jq_j + m_kq_k )( m_j + m_k )

It would be helpful if some one could help.

Answer 1

It should be an r in the notation that they used before. These are the position vectors of the two objects. And a hint: If you are confused next time, try finding different sources. I'm sure the definition of the center of mass vector can be found elsewhere.