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Tensor algebras and displacement structure. IV. Invariant kernels

T. Banks·T. Constantinescu·Nermine El-Sissi
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Abstract

In this paper we investigate the class of invariant positive definite kernels on the free semigroup on N generators. We provide a combinatorial description of the positivity of the kernel in terms of Dyck paths and then we find a displacement equation that encodes the invariance property of the kernel.

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T. Banks, T. Constantinescu, Nermine El-Sissi. 2004-10-22. Tensor algebras and displacement structure. IV. Invariant kernels. https://arxiv.org/abs/math/0410491

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