#include <fstream>

using namespace std;

ifstream cin("fractii.in");
ofstream cout("fractii.out");

bool gcd(int a, int b)
{
    int r;
    while(b)
    {
        r = b;
        b = a%b;
        a = r;
    }
    if(a == 1)
        return 1;
    return 0;
}

int main()
{
    int n, i, j, s = 0;
    cin >> n;
    for(i = 2; i <= n; i++)
        for(j = i + 1; j <= n; j++)
            if(!gcd(i, j))
            {
                s++;
            }
    s = n*(n-1) - 2*s + 1;
    cout << s;
    return 0;
}