A non-hyponormal operator generating Stieltjes moment sequences

Z. J. Jablonski, I. B. Jung, J. Stochel

A linear operator $S$ in a complex Hilbert space $\hh$ for which the set $\dzn{S}$ of its $C^{\infty }$-vectors is dense in $\hh$ and $\{\Vert S^{n}f{\Vert }^2{\}}_{n=0}^{\infty }$ is a Stieltjes mom…