#include <fstream>
using namespace std;

int prime(int a, int b)
{
    if(a % b || b == 1) return 1;
    else return 0;
}

int main()
{
    ifstream in("fractii.in");
    ofstream out("fractii.out");

    int n;
    in >> n;
    in.close();

    int nr = 0;
    for(int i = 1; i < n; i++)
        for(int j = 1; j < n; j++)
            if(prime(i, j)) nr++;

    out << nr;
    out.close();

    return 0;
}