#include <fstream>


using namespace std;

ifstream fin("fractii.in");
ofstream gout("fractii.out");

int prime(int i)
{
    int r,a,b, cnt=0;
    for (int j=2;j<=i-1;j++)
    {
        a=i;
        b=j;
        do{
        r=a%b;
        a=b;
        b=r;
        }while(r);
        if (a==1)
            cnt++;
    }
    return cnt;
}

int main()
{
    int n, i, cnt;
    fin >> n;
    cnt = 2*n - 1;
    for (i=n;i>=2;i--)
        cnt += 2*prime(i);
    gout << cnt;
}