The Sum of the mth Powers of the Zeros of the Generalized Bessel Polynomial

Let σ(n)m(a) be the sum of the mth powers of the zeros of the generalized Bessel polynomial yn(x; a). Motivated by an open problem of E. Grosswald, we find formulas for σ(n)m(a) and σ(n)−m(a). These results generalize previous formulas of the writer for a = 2.