Analytic continuation of Lauricella's function F D (N) for variables close to unit near hyperplanes {z j = z l }

Abstract

For the Lauricella hypergeometric function with an arbitrary number of variables , we construct formulas for analytic continuation into the vicinity of hyperplanes and their intersections providing that all variables are close to unit. Such formulas represent the function near the point as linear combinations of N–multiple hypergeometric series that are solutions of the same system of partial differential equations as . Such series are the N–dimensional analog of the Kummer solutions known for the Gauss equation. The constructed analytical continuation formulas allow one to effectively calculate the function outside the unit polydisk.