2 z + asin(3*z)
z^2 + asin(3*z)
3 2*z + ------------- __________ / 2 \/ 1 - 9*z
27*z 2 + ------------- 3/2 / 2\ \1 - 9*z /
/ 2 \ | 27*z | 27*|1 + --------| | 2| \ 1 - 9*z / ----------------- 3/2 / 2\ \1 - 9*z /