The moment generating function (hence the cumulant generating function)
of the distribution is given in the refence below.
The computations method used is proved analytically up to n=3 but it is
seen to behave correctly up to the order which was checked (n=8).
References
Azzalini, A. (1985).
A class of distributions which includes the normal ones.
Scand. J. Statist.12, 171-178.