We apply a simple observation to show that the generalized Dicke states can
be determined from their reduced subsystems. In this framework, it is
sufficient to calculate the expression for only the diagonal elements of the
reudced density matrices in terms of the state coefficients. We prove that the
correlation in generalized Dicke states ∣GDN(ℓ)> can be reduced to
2ℓ-partite level. Application to the Quantum Marginal Problem is also
discussed.Comment: 12 pages, single column; accepted in J. Phys. A as FT