The compositional inverse (with respect to x) of y(t, x) = x - t*(exp(x) - 1)
is 1/(1-t)*y + t/(1-t)^3*y^2/2! + (t+2*t^2)/(1-t)^5*y^3/3! + (t+8*t^2+6*t^3)/(1-t)^7*y^4/4! + ... Apparently multivariate power series rings do not know how to reverse a series. Perhaps there is a workaround? Thanks! -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-support/b70394ce-3b11-412e-8a1d-3acd89ace6c6n%40googlegroups.com.