The AM of the series 1, 2, 4, 8, 16, . . ., 2n is
2n−1n
2n+1−1n+1
2n+1n
2n−1n+1
The required AM isX¯=1+2+22+23+⋯+2nn+1=2n+1−1(n+1)(2−1)=2n+1−1n+1