complex iteration (complex "height")

[Ivars]

My brain is already overstretched... I think I need some software that can calculate infinitely many logarithms

Ivars - besides the answer of Henryk, which is quite right - why don't you use Pari/GP? It's free (and I 've made a free GUI (Windows) for it) search for "Pari" or "Paritty". Using Paritty you could also get my matrix-routines for a first start.

Gottfried

Thank You , that is practical. Downloaded version 2.3.3, Windows. Seems simpler to start with than Octave,Scilab, and more comlicated then gnuplot (those I have tried, I actually liked gnuplot best as it gives pictures of functions of exponents (like Lambert( x^(1/x) easily). The simplest are Xnumbers for Excel. Where can I fetch Your GUI to make life even simpler?

I already Love PARI; intuitively easy, great tutorial, gives power series if You type log(1+x) or exp(x). Just this Lambert function-but if its not there, we have to maneuvre around it-maybe its worth it?

Ivars