maybe the bessel functions are some complicated function of the exponential function, logarithm function... or maybe there's a relation between two or more transcendental functions. Is there a way to prove it?
I was thinking that given two power series (or generalized power series) $f(x)$ and $g(x)$ on the infinite dimensional space of analytic real functions (or even complex), there should be an infinite number of functions $F$ such that $F(f(x),g(x))=0$ so no two transcendental function are independent and the so-called special functions are nothing more than a complicated functions applied to the exponential function for example.