ILL 1985 Problem 3

A function f has the following property: If $k > 1, j > 1$ , and $\gcd(k, j) = m$ , then $f(kj) = f(m) (f\left(\frac km\right) + f\left(\frac jm\right))$ . What values can $f(1984)$ and $f(1985)$ take?