#include <fstream>
#define inFile "fractii.in"
#define outFile "fractii.out"
using namespace std;

ifstream in(inFile);
ofstream out(outFile);

int s, n;

int cmmdc(int a, int b)
{
    int c;
    while (b)
    {
        c = a % b;
        a = b;
        b = c;
    }
    return a;
}

void citire()
{
    in>>n;
}

void back()
{
    for(int numitor = 2; numitor <= n; numitor++)
    {
        for(int numarator = 2; numarator <= n; numarator++)
        {
            if(cmmdc(numitor, numarator) == 1)
            {
                s++;
            }
        }
    }
}

int main()
{
    citire();
    back();
    s = s + 2*n - 1;
    out<<s;
    return 0;
}