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arXiv · 1707.02404

Existence results for primitive elements in cubic and quartic extensions of a finite field

Geoff Bailey·Stephen D. Cohen·Nicole Sutherland·Tim Trudgian
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Abstract

With $\Fq$ the finite field of $q$ elements, we investigate the following question. If $\gamma$ generates $\Fqn$ over $\Fq$ and $\beta$ is a non-zero element of $\Fqn$, is there always an $a \in \Fq$ such that $\beta(\gamma + a)$ is a primitive element? We resolve this case when $n=3$, thereby proving a conjecture by Cohen. We also improve substantially on what is known when $n=4$.

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Geoff Bailey, Stephen D. Cohen, Nicole Sutherland, Tim Trudgian. 2017-07-08. Existence results for primitive elements in cubic and quartic extensions of a finite field. https://doi.org/10.1090/mcom/3357

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