Number theory/Ordinary differential equations
On the mock-theta behavior of Appell–Lerch series
[Sur le comportement mock thêta de séries d'Appell–Lerch]
Comptes Rendus. Mathématique, Tome 353 (2015) no. 12, pp. 1067-1073.

Le but de cette Note est de trouver une manière naturelle d'écrire chaque série d'Appell–Lerch du premier ordre au moyen de deux fonctions dont le comportement asymptotique devient plus simple. On démontre qu'une telle écriture existe, avec seulement des fonctions de type thêta et celles qui ont un développement asymptotique Gevrey. Afin de faciliter l'exposé, nous introduisons trois types de fonctions du genre thêta, qui seront appelés type thêta, type faux thêta et type mock thêta.

The goal of this paper is to find one natural way to write the first order Appell–Lerch series in terms of two functions whose asymptotic behavior becomes simple. It is shown that such writing exists, using only theta-like functions and functions having a Gevrey asymptotic expansion. In order of simplify the presentation, we introduce three types of theta-like functions that will be called theta-type, false theta-type and mock theta-type.

Reçu le :
Accepté le :
Publié le :
DOI : 10.1016/j.crma.2015.09.028
Zhang, Changgui 1

1 Laboratoire Paul-Painlevé, CNRS UMR 8524, UFR de mathématiques, Université Lille-1 (USTL), Cité scientifique, 59655 Villeneuve d'Ascq cedex, France
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Zhang, Changgui. On the mock-theta behavior of Appell–Lerch series. Comptes Rendus. Mathématique, Tome 353 (2015) no. 12, pp. 1067-1073. doi : 10.1016/j.crma.2015.09.028. http://www.numdam.org/articles/10.1016/j.crma.2015.09.028/

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