Hypergeometric 1F0
From specialfunctionswiki
The hypergeometric ${}_1F_0$ function is defined by the series $${}_1F_0(a;;z)=\displaystyle\sum_{k=0}^{\infty} \dfrac{(a)_k z^k}{k!},$$ where $(a)_k$ denotes the Pochhammer symbol and $k!$ denotes the factorial.