Task: Text Categorization
Input (English): Fermat's little theorem can be used to prove that this function of a prime minus one equals negative one modulo that prime according to Wilson's theorem. When this function's argument is downshifted by one, the gamma function results. The natural log of this function of n is equal to n log n minus n for very large n according to [*] Stirling's approximation. This function appears in the denominator of all the terms of the Taylor series, and it is used to calculate binomial coefficients with combinations. For 10 points, name this function of n equal to the product of all positive integers less than or equal to n, symbolized with an exclamation point.
Output (English): Science