How to guess a multivariable function's PDE?

[Gottfried]

i find that tetration is a math forum, so i ask here.

Well, originally its about tetration and associated topics.
But maybe if you are more specific we can see what we can do anyway.

Not me. I find this appearence simply rude. Why can't people respect if some others want to make them a forum about a certain topic? And want have a certain concentration, athmosphere, familiarity and mathematical level with this?

For me: this thread is spam (we had also another one recently).

Gottfried