The Newton Polyhedron and positivity of ${}_2{F}_3$ hypergeometric functions

Yong-Kum Cho, Seok-Young Chung

As for the ${}_2{F}_3$ hypergeometric function of the form \begin{equation*} {}_2F_3\left[\begin{array}{c} a_1, a_2\\ b_1, b_2, b_3\end{array}\biggr| -x^2\right]\qquad(x>0), \end{equ…