Norm approximation by polynomials in some weighted Bergman spaces (Q1614774)

In this paper the author shows that the polynomials are dense in weighted Bergman spaces in the unit disc whose weights are superbiharmonic functions and vanish in an average sense at the boundary. This result yields an alternative proof of the Aleman Richter-Sundberg Beurling-type theorem related to the zero-based invariant subspaces in the classical Bergman space. Further, the author obtains several consequences.