#include <iostream>
#include <fstream>
using namespace std;

int main()
{
    ifstream fin("fractii.in", ios::in);
    ofstream fout("fractii.out", ios::out);
    int P, Q, N, nr, i, j;
    fin >> N;
    nr = 0;
    for (P = 2; P <= N; P++)
    {
        nr = nr + N;
        for (i = 1; i <= P / N; i++)
            if(P*i<=N)
                nr--;

    }
    fout << nr << endl;
    return 0;
}