This function returns Stirling's approximation of the factorial of the given number

factorial_stirling(n)

Returns: int

Stirling's approximation (or Stirling's formula) is an approximation for factorials. It is a good approximation, leading to accurate results even for small values of n. This function is much way faster then factorial.

int value = factorial_stirling(5);

This Function will set value to 118. Correct result of 5! is 120, so the acuraccy for number 5 is 98,3%.

int value = factorial_stirling(10);

This Function will set value to 3598695. Correct result of 10! is 3628800, so the acuraccy for number 10 is 99,17%.

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