You are given an integer \(N\).

Find the sum of \(\lfloor \frac{i}{j} \rfloor\) for all pairs of \(i\),\(j\) ( \(1 \leq i \leq N\) and \(1 \leq j \leq N\)), such that \(i\) and \(j\) are co-prime.

Input Format:

A single line contaning an integer \(N\).

Constraints:

\(1 \leq N \leq 10^5\)

Output format:

Print the required sum.