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A functional equation arising from multiplication of quantum integers

Melvyn B. Nathanson
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Abstract

For the quantum integer $[n]_q = 1+q+...+q^{n-1}$ there is a natural polynomial multiplication $*_q$ such that $[m]_q *_q [n]_q = [mn]_q$. This multiplication leads to the functional equation $f_{mn}(q) = f_m(q)f_n(q^m),$ defined on a given sequence $\mathcal(F)=\{f_n(q)\}_{n=1}^{\infty}$ of polynomials. This paper contains various results concerning the classification and construction of polynomial sequences that satisfy the functional equation, as well as a list of open problems that arise fromthe classification.

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Melvyn B. Nathanson. 2002-03-21. A functional equation arising from multiplication of quantum integers. https://arxiv.org/abs/math/0203217

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