5 + (9*(1/(2*n^2) - 1/(2*n)))/125 + (27*(1/(6*n^3) - 1/(2*n^2) + 1/(3*n)))/
  3125 + 3/(5*n)
11/24
(4 + 3*x)/9 + E^x*C[1] + E^(3*x)*C[2]