"Log-polar" (see also wikipedia https://en.wikipedia.org/wiki/Log-polar_coordinates ) representation might fill the prerequisites a tiny bit better.

For instance the regular tetration with a complex fixpoint, curving around the fixpoint can then be approximated by linear interpolation and that interpolation agrees better and better with the regular tetration if the coordinate is translated into vicinity of the fixpoint using the functional equation. I have a picture of this in my comparision "5 methods for interpolation" ( http://go.helms-net.de/math/tetdocs/Comp...ations.pdf ) posted here earlier.

For instance the regular tetration with a complex fixpoint, curving around the fixpoint can then be approximated by linear interpolation and that interpolation agrees better and better with the regular tetration if the coordinate is translated into vicinity of the fixpoint using the functional equation. I have a picture of this in my comparision "5 methods for interpolation" ( http://go.helms-net.de/math/tetdocs/Comp...ations.pdf ) posted here earlier.

Gottfried Helms, Kassel