A recurrence

[Brendan McKay]

Anyone know how to solve recurrences like this?

s(0) = 1
s(1) = -x-1
s(i) = (i-1)*ss(i-2) - (i+x)*ss(i-1)   (i >= 2)

For example:
s(2) = x^2+3x+3
s(3) = -x^3-6x^2-14x-11

Thanks, Brendan.