MathDB
Math Prize 2010 Problem 13

Source:

November 14, 2010
trigonometry

Problem Statement

For every positive integer nn, define SnS_n to be the sum Sn=k=12010(cosk!π2010)n. S_n = \sum_{k = 1}^{2010} \left( \cos \frac{k! \, \pi}{2010} \right)^n . As nn approaches infinity, what value does SnS_n approach?