Suppose {an}n=1∞ is a sequence. The partial sums {sn}n=1∞ are defined by
sn=i=1∑nai.
The Cesàro sums are then defined as {An}n=1∞, where
An=n1⋅i=1∑nsi.
Let an=(−1)n+1. What is the limit of the Cesàro sums of {an}n=1∞ as n goes to infinity?