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arXiv · 1808.10440

Visibly irreducible polynomials over finite fields

Evan M. O'Dorney
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Abstract

H. Lenstra has pointed out that a cubic polynomial of the form (x-a)(x-b)(x-c) + r(x-d)(x-e), where {a,b,c,d,e} is some permutation of {0,1,2,3,4}, is irreducible modulo 5 because every possible linear factor divides one summand but not the other. We classify polynomials over finite fields that admit an irreducibility proof with this structure.

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Evan M. O'Dorney. 2018-08-30. Visibly irreducible polynomials over finite fields. https://doi.org/10.1080/00029890.2020.1677103

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