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arXiv · 0807.0385

A bilinear form relating two Leonard systems

Hajime Tanaka
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Abstract

Let $\Phi$, $\Phi'$ be Leonard systems over a field $\mathbb{K}$, and $V$, $V'$ the vector spaces underlying $\Phi$, $\Phi'$, respectively. In this paper, we introduce and discuss a balanced bilinear form on $V\times V'$. Such a form naturally arises in the study of $Q$-polynomial distance-regular graphs. We characterize a balanced bilinear form from several points of view.

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Hajime Tanaka. 2008-07-02. A bilinear form relating two Leonard systems. https://doi.org/10.1016/j.laa.2009.06.012

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