Kummer's Hypergeometric Theorem/Lemma 2

Lemma for Kummer's Hypergeometric Theorem

 * $\ds \lim_{y \mathop \to \infty} \dfrac {\paren {y + \dfrac n 2 + 1}^{\overline x} } {\paren {y + n + 1}^{\overline x} } = 1$

where $y^{\overline x}$ denotes the $x$th rising factorial of $y$.