A note on the spectral for real Hankel matrices

摘要

Driessel [K.R. Driessel, Private communication, 1991] posed the following open-problem: Characterize all n-tuples of real numbers which can serve as n-tuples of eigenvalues of some real Hankel matrices. Miroslav Fiedler has given two necessary conditions for this problem in [M. Fiedler, Spectral properties of real Hankel matrices, Contemporary Mathematics 280 (2001) 313–320]. In this paper we shall completely present the necessary conditions for such spectral and generalize partial results of [M. Fiedler, Spectral properties of real Hankel matrices, Contemporary Mathematics 280 (2001) 313–320].