where is a Pochhammer symbol and is a confluent hypergeometric function of the first kind.
Poisson-Charlier Function
See also
Poisson-Charlier PolynomialExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Poisson-Charlier Function." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Poisson-CharlierFunction.html