  Correlations of different azimuthal flow harmonics $v_n$ and symmetry planes
$\Psi_n$ can add constraints to theoretical models, and probe aspects of the
system that are independent of the traditional single-harmonic measurements.
Using NeXSPheRIO, a hydrodynamical model which has accurately reproduced a
large set of single-harmonic correlations at RHIC, we make predictions of these
new observables for 200 A GeV Au+Au Collisions, providing an important baseline
for comparison to correlations of flow harmonics, which contain non-trivial
information about the initial state. We also point out how to properly compare
theoretical calculations to measurements using wide centrality bins and
non-trivial event weighting.
