Is there a simpler expression for $f(f(f(...f(x)...)))$ (total n '$f$') ?
Thank you.
Is there a simpler expression for $f(f(f(...f(x)...)))$ (total n '$f$') ?
Thank you.
The notation $f^n=\underset{\text{$n$-times}}{\underbrace{f\circ \dots \circ f}}$ is commonly used. (So $f(f(\dots f(x)\dots))=f^n(x)$.)
Occasionally this might be confused with $(f(x))^n$, i.e. the $n$-th power of the value $f(x)$, but it is usually clear from the context which of the two is meant.
See Wikipedia article Iterated function.