$f^{\alpha }\left( \overrightarrow {0}\right) +f^{\beta }\left( \overrightarrow {0}\right) =f^{\alpha \beta +\alpha +\beta }\left( \overrightarrow {0}\right)$ Is there a function $f$ from $R^{\infty}$ to $R^{\infty}$ that satisfies this equation for all natural ${\alpha}$ and ${\beta}$ ? I already know that any function that has $f\left( \overrightarrow {0}\right)= \overrightarrow {0}$ satisfies the equation, so are there any other functions that satisfy the equation? Thank you in advance! *My phrasing for this being a "funtional equation" was flawed. All I really wanted to know was the existance of a function that satisfies the equation above. *The superscripts indicate iterations of $f$.