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arXiv · 1912.00593

Logarithmic A-hypergeometric series

Mutsumi Saito
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Abstract

The method of Frobenius is a standard technique to construct series solutions of an ordinary linear differential equation around a regular singular point. In the classical case, when the roots of the indicial polynomial are separated by an integer, logarithmic solutions can be constructed by means of perturbation of a root. The method for a regular A-hypergeometric system is a theme of the book by Saito, Sturmfels, and Takayama. Whereas they perturbed a parameter vector to obtain logarithmic A-hypergeometric series solutions, we adopt a different perturbation in this paper.

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Mutsumi Saito. 2019-12-02. Logarithmic A-hypergeometric series. https://arxiv.org/abs/1912.00593

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