09/27/2009, 12:52 AM
I've heard that the series obtained for \( f^t(z) \) for \( f(z) = u^z - 1 \) with respect to z at z = 0 do not converge but diverge and diverge very strongly. I suspect this is because at fractional z (iteration number), the fixed point z = 0 is also a branch point at such iteration numbers ("heights", though I prefer to reserve that term for only referring to the second parameter of tetration), and so f is not analytic there. I'm not sure if or how this would carry over to/affect the Schroeder function.

