05/02/2009, 08:32 AM
So do you mean the following?
\( {}^{\circ 2}f(x) = f^{f(x)}(x) \)
\( {}^{\circ 3}f(x) = f^{f^{f(x)}(x)}(x) \)
\( {}^{\circ 4}f(x) = f^{f^{f^{f(x)}(x)}(x)}(x) \)
I know I've seen this somewhere... I want to say this paper but I can't find it.
\( {}^{\circ 2}f(x) = f^{f(x)}(x) \)
\( {}^{\circ 3}f(x) = f^{f^{f(x)}(x)}(x) \)
\( {}^{\circ 4}f(x) = f^{f^{f^{f(x)}(x)}(x)}(x) \)
I know I've seen this somewhere... I want to say this paper but I can't find it.

