Technical data for this type of fractal : click here.
For the factal here :
fn1 = ident(), fn2 = cotan(), fn3 = cotanh(), fn4 = flip()
real(p1) = 1, imag(p1) = -4, real(p2) = 1, imag(p2) = 1, real(p3) = 2, imag(p3) = 1
Note.
The flip() function swaps the real and imaginery components
of the complex number, e.g. (4,5) becomes (5,4).