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arXiv · 2412.00482

On extremal problems of Delsarte type for positive definite functions on LCA groups

Elena E. Berdysheva·Mita D. Ramabulana·Szilárd Gy. Révész
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Abstract

A unifying framework for some extremal problems on locally compact Abelian groups is considered, special cases of which include the Delsarte and Tur\'an extremal problems. A slight variation of the extremal problem is introduced and the different formulations are studied for equivalence. Extending previous work, a general result on existence of extremal functions for the new variant is proved under a certain general topological condition.

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Elena E. Berdysheva, Mita D. Ramabulana, Szilárd Gy. Révész. 2024-11-30. On extremal problems of Delsarte type for positive definite functions on LCA groups. https://arxiv.org/abs/2412.00482

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