Calculate the value over sum 2^n * x_n
Source: IMO Longlist 1989, Problem 38
September 18, 2008
inductionalgebra solvedalgebra
Problem Statement
A sequence of real numbers is defined as follows: x_0 \equal{} 1989 and for each
x_n \equal{} \minus{} \frac{1989}{n} \sum^{n\minus{}1}_{k\equal{}0} x_k.
Calculate the value of \sum^{1989}_{n\equal{}0} 2^n x_n.