Totient Sum
Let $S(n,m) = \sum\phi(n \times i)$ for $1 \leq i \leq m$. ($\phi$ is Euler's totient function)
You are given that $S(510510,10^6)= 45480596821125120$.
Find $S(510510,10^{11})$.
Give the last $9$ digits of your answer.
Let $S(n,m) = \sum\phi(n \times i)$ for $1 \leq i \leq m$. ($\phi$ is Euler's totient function)
You are given that $S(510510,10^6)= 45480596821125120$.
Find $S(510510,10^{11})$.
Give the last $9$ digits of your answer.