Publish Date:
Let $A_q(n)$ be the number of subsets, $B$, of the set $\{1, 2, ..., q \cdot n\}$ that satisfy two conditions:
1) $B$ has exactly $n$ elements;
2) the sum of the elements of $B$ is divisible by $n$.
E.g. $A_2(5)=52$ and $A_3(5)=603$.
Let $S_q(L)$ be $\sum A_q(p)$ where the sum is taken over all primes $p \le L$.Find $S_2(10^8)+S_3(10^8)$. Give your answer modulo $1\,000\,000\,009$.
Press F12 and use the "Console" tab to view the output of your codes.