Selfdual skew cyclic codes

Xavier Caruso; Fabrice Drain

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arXiv · 2410.12340

Selfdual skew cyclic codes

Xavier Caruso·Fabrice Drain

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Abstract

Given a finite extension $K/F$ of degree $r$ of a finite field $F$, we enumerate all selfdual skew cyclic codes in the Ore quotient ring $K[X;\text{Frob}]/(X^{rk}-1)$ for any positive integer $k$ coprime to the characteristic $p$ (separable case). We also provide an enumeration algorithm when $k$ is a power of $p$ (purely inseparable case), at the cost of some redundancies. Our approach is based on an explicit bijection between skew cyclic codes, on the one hand, and certain families of $F$-linear subspaces of some extensions of $K$. Finally, we report on an implementation in SageMath.

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Xavier Caruso, Fabrice Drain. 2024-10-16. Selfdual skew cyclic codes. https://arxiv.org/abs/2410.12340

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