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arXiv · 2212.10824

Bivariate $P$-polynomial association schemes

P. -A. Bernard·N. Crampe·L. Poulain d'Andecy·L. Vinet·M. Zaimi
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Abstract

Bivariate P-polynomial association scheme of type $(α,β)$ are defined as a generalization of the P-polynomial association schemes. This generalization is shown to be equivalent to a set of conditions on the intersection parameters. A number of known higher rank association schemes are seen to belong to this broad class. Bivariate Q-polynomial association schemes are similarly defined.

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P. -A. Bernard, N. Crampe, L. Poulain d'Andecy, L. Vinet, M. Zaimi. 2024-07-09. Bivariate $P$-polynomial association schemes. https://doi.org/10.5802/alco.344

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