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arXiv · 1909.06409

Scalar $q$-subresultants and Dickson matrices

Bence Csajbók
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Abstract

Following the ideas of Ore and Li we study $q$-analogues of scalar subresultants and show how these results can be applied to determine the rank of an $\mathbb{F}_q$-linear transformation $f$ of $\mathbb{F}_{q^n}$. As an application we show how certain minors of the Dickson matrix $D(f)$, associated with $f$, determine the rank of $D(f)$ and hence the rank of $f$.

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Bence Csajbók. 2019-09-13. Scalar $q$-subresultants and Dickson matrices. https://doi.org/10.1016/j.jalgebra.2019.10.056

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