Task: Text Categorization
Input (English): sum of the squares of the reciprocals of this function evaluated at the nonnegative integers is equal to the modified Bessel function of the first kind at x=2. The Leviathan Number is found by evaluating this function at 10 to the 666th power. The rising type can be represented with the Pochhammer Symbol. Wilson's Theorem states that this function of any prime minus 1 is also congruent to -1 modulo that prime. Legendre's theorem provides a corollary to determine the number of (*) trailing zeroes of this function evaluated at nonnegative integers. When this function is evaluated at large numbers, Stirling's approximation is used. The gamma function extends this function to all complex numbers other than negative integers. For 10 points, name this function that, for positive integers n, is the product from 1 to n, and which is represented by an exclamation point.
Output (English): Science