希尔伯特不等式中的最佳常数

IF 0.8 4区 数学 Q2 MATHEMATICS
Ole Fredrik Brevig
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引用次数: 1

摘要

建立∑m=1∞∑n=1∞aman¯mn(max(m,n))3≤43∑m=1∞|am|2对复数a=(a1,a2,…)的每一个平方可和数列都成立,并且常数4/3不能被任何更小的数代替。我们的证明植根于1911年一篇关于舒尔的双线性形式的开创性论文,出于解释性的原因,我们包括了对他的方法的阐述。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
The best constant in a Hilbert-type inequality

We establish that m=1n=1aman¯mn(max(m,n))343m=1|am|2holds for every square-summable sequence of complex numbers a=(a1,a2,) and that the constant 4/3 cannot be replaced by any smaller number. Our proof is rooted in a seminal 1911 paper concerning bilinear forms due to Schur, and we include for expositional reasons an elaboration on his approach.

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来源期刊
CiteScore
1.30
自引率
0.00%
发文量
41
审稿时长
40 days
期刊介绍: Our aim is to publish papers of interest to a wide mathematical audience. Our main interest is in expository articles that make high-level research results more widely accessible. In general, material submitted should be at least at the graduate level.Main articles must be written in such a way that a graduate-level research student interested in the topic of the paper can read them profitably. When the topic is quite specialized, or the main focus is a narrow research result, the paper is probably not appropriate for this journal. Most original research articles are not suitable for this journal, unless they have particularly broad appeal.Mathematical notes can be more focused than main articles. These should not simply be short research articles, but should address a mathematical question with reasonably broad appeal. Elementary solutions of elementary problems are typically not appropriate. Neither are overly technical papers, which should best be submitted to a specialized research journal.Clarity of exposition, accuracy of details and the relevance and interest of the subject matter will be the decisive factors in our acceptance of an article for publication. Submitted papers are subject to a quick overview before entering into a more detailed review process. All published papers have been refereed.
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