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arXiv · 1810.03142

A note on the stability of trinomials over finite fields

Omran Ahmadi·Kosrov Monsef-Shokri
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Abstract

A polynomial $f(x)$ over a field $K$ is called stable if all of its iterates are irreducible over $K$. In this paper we study the stability of trinomials over finite fields. Specially, we show that if $f(x)$ is a trinomial of even degree over the binary field $\mathbb{F}_2$, then $f(x)$ is not stable. We prove a similar result for some families of monic trinomials over finite fields of odd characteristic. These results are obtained towards the resolution of a conjecture on the instability of polynomials over finite fields whose degrees are divisible by the characteristic of the underlying field.

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Omran Ahmadi, Kosrov Monsef-Shokri. 2018-10-07. A note on the stability of trinomials over finite fields. https://arxiv.org/abs/1810.03142

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