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arXiv · 1609.07677

Generalizations of self-reciprocal polynomials

Sandro Mattarei·Marco Pizzato
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Abstract

A formula for the number of monic irreducible self-reciprocal polynomials, of a given degree over a finite field, was given by Carlitz in 1967. In 2011 Ahmadi showed that Carlitz's formula extends, essentially without change, to a count of irreducible polynomials arising through an arbitrary quadratic transformation. In the present paper we provide an explanation for this extension, and a simpler proof of Ahmadi's result, by a reduction to the known special case of self-reciprocal polynomials and a minor variation. We also prove further results on polynomials arising through a quadratic transformation, and through some special transformations of higher degree.

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Sandro Mattarei, Marco Pizzato. 2016-09-24. Generalizations of self-reciprocal polynomials. https://arxiv.org/abs/1609.07677

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