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The Proof of Stirling's approximation

Stirling公式的证明

When describing the time complexity of an algorithm, we often use Big O notation to describe the growth of computation with the size of the problem. For a factorial $n!$ of positive integers, this time complexity is $O(n)$ if a general recursive implementation is used, which represents a linear increase in computational effort as $n$ grows. When $n$ is large,...