CMB statistical anisotropy, multipole vectors, and the influence of the dipole

A simple algorithm which gives the multipole vectors in terms of the roots of a polynomial is given. We find that the reported alignment of the low l multipole vectors can be summarized as an orthogonality of these with the dipole direction. This orthogonality is not only present in l=2 and 3 but also for l=5 and higher. This alignment is likely due to nonlinearity in the data processing. Our results are based on the 3 yr Wilkinson Microwave Anisotropy Probe data, we also list corresponding results for the first year data.