Question 1025812
{{{sum(a[k], k=1, n)/n = a}}} ==> {{{sum((a[k]+2^k), k=1, n)/n = sum(a[k], k=1, n)/n+sum(2^k, k=1,n)/n = a + (1/n)*2*((1-2^n)/(1-2))}}}

=  {{{a + (2/n)(2^n-1)}}}, or {{{a + (2(2^n-1))/n}}}