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arXiv · 2312.17009

Continued fractions for $q$-deformed real numbers, $\{-1,0,1\}$-Hankel determinants, and Somos-Gale-Robinson sequences

Valentin Ovsienko·Emmanuel Pedon
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Abstract

$q$-deformed real numbers are power series with integer coefficients. We study Stieltjes and Jacobi type continued fraction expansions of $q$-deformed real numbers and find many new examples of such continued fractions. We also investigate the corresponding sequences of Hankel determinants and find an infinite family of power series for which several of the first sequences of Hankel determinants consist of $-1,0$ and $1$ only. These Hankel sequences satisfy Somos and Gale-Robinson recurrences.

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Valentin Ovsienko, Emmanuel Pedon. 2023-12-28. Continued fractions for $q$-deformed real numbers, $\{-1,0,1\}$-Hankel determinants, and Somos-Gale-Robinson sequences. https://arxiv.org/abs/2312.17009

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