In a paper from 2016 D. R. Yafaev considers Hankel operators associated with Hamburger moment sequences $$q_n$$ q n and claims that the corresponding Hankel form is closable if and only if the moment sequence tends to 0. The claim is not correct, since we prove closability for any indeterminate moment sequence but also for certain determinate moment sequences corresponding to measures with finite index of determinacy. In an Erratum Yafaev (Integr Equ Oper Theory, to appear) has proved the result under quasi-analyticity assumptions, which imply that the moment sequence is determinate.

中文翻译：

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可闭合 Hankel 算子和矩问题

在 2016 年 DR Yafaev 的一篇论文中，考虑了与汉堡矩序列 $$q_n$$ qn 相关的 Hankel 算子，并声称相应的 Hankel 形式是可闭合的当且仅当矩序列趋于 0 时。这种说法是不正确的，因为我们证明任何不确定矩序列的可闭合性，也包括对应于具有有限确定性指数的测度的某些确定矩序列。在一个勘误表中，Yafaev（Integr Equ Oper Theory，出现）证明了准分析性假设下的结果，这意味着矩序列是确定的。