Question 98
An integer valued function $f(n)$ is multiplicative (that means $f(ab) = f(a)f(b)$ for all coprime $a$ and $b$) and satisfies the equation
$$
f(m + k - 3) = f(m) + f(k) - f(3) \quad \text{for all primes } m \text{ and } k.
$$
Find $f(11)$.
$$
f(m + k - 3) = f(m) + f(k) - f(3) \quad \text{for all primes } m \text{ and } k.
$$
Find $f(11)$.