z'=Exp[I*2*Pi/m]*(z^2+c)
Rotaion by a cyclotomic angle power of 1/m: 360 degrees/ m
z[n]=Exp[I*2*Pi/m]*(z[n-1]^3-z[n-1]^2+c)
You have to distinguish what you mean by "3d dimensional".
Regular Mandlbrots are 3d if you take the iteration color as height.
I doubt this is your meaning.
There is a program you can buy for doing quaternion Mandelbrots and
Julias by Terry Gintz.
Quaternions are sometimes called "hypercomplex numbers"
Akira bergman has also his H-numbers.
It is called Clifford algebra after the guy who came after Hamilton
and increased the number of dimensions.
There are octonions with eight dimensions even.
http://www.google.com/search?hl=en&lr=&safe=off&q=octonions+fractals&btnG=Search
Basically:
z1=x1+I*y1
z2=x2+I*y2
q=x1+I*y1+J*(x2+I*x2)=x1+I*y1+J*x2+K*x2
J*I==K
I^2=-1
J^2=-1
k^2=-1
q*qstar=(x1+I*y1+J*x2+K*x2)*(x1-I*y1-J*x2-K*x2)=x1^2+y1^2+x2^2+y2^2
Lord Hamilton's quaternions were first created to make spherical
geometry easier...
They turn out what one might call taffy pull sets in 3d.
http://www.google.com/search?hl=en&q=terry+Gintz+quaternions&btnG=Google+Search
http://home.att.net/~d.a.hasson/quasz_for_dummies.html
In four dimensions you have formulas like:
q[n]=Exp[I*2*Pi*i]/L]*Exp[J*2*Pi*i]/M]*Exp[K*2*Pi*i]/N]*(q[n-1]^2+c)
That's three orthogonal directions of rotation instead of just one.
Post by Sondawhat would happend to mandelbrot set if we would change axes of surface
from (-1)^0, (-1)^(1/2) (real numbers and i ) to (-1)^(1/3),
(-1)^(1/7).
possibly we can have "true" three dimensional fractal with axes for
example
(-1)^(1/7), (-1)^(1/4), (-1)^(1/13) and sequence Zn+1=Zn^3 - Zn^2 + C.