On the integrality of factorial ratios and mirror maps

Alan Adolphson; Steven Sperber

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arXiv · 1802.08348

On the integrality of factorial ratios and mirror maps

Alan Adolphson·Steven Sperber

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Abstract

Landau has characterized the integrality of certain ratios of factorials. Delaygue has characterized the integrality of the Taylor coefficients of certain mirror maps constructed from series involving those ratios. Using the $A$-hypergeometric point of view, we express those characterizations in terms of the nonexistence of interior points in multiples of the associated lattice polytope.

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Alan Adolphson, Steven Sperber. 2018-02-22. On the integrality of factorial ratios and mirror maps. https://arxiv.org/abs/1802.08348

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