Stirling's formula derived simply
math.CO
/ Authors
/ Abstract
Stirling's formula, the asymptotic expansion of $n!$ for $n$ large, or of $Γ(z)$ for $z\to \infty$, is derived directly from the recursion equation $Γ(z+1) =z Γ(s)$ and the normalization condition $Γ({1/2}) =\sqrtπ$.