#include <fstream>
using namespace std;
int cmmdc (int, int);
ifstream fin("date.in");
ofstream fout("date.out");
int main ()
{
    unsigned n, cont, r, b, c;
    fin >> n;
    cont = 2*n-1;
    for (unsigned i = 2; i <= n; i++)
    {
        b = i;
        for (unsigned j = 2; j <= n; j++)
        {
            c = j;
            r = cmmdc(b, c);
            if (r == 1) cont++;
        }
    }
    fout << cont;
    fin.close();
    fout.close();
    return 0;
}
int cmmdc(int b, int c)
{
    int r;
    while (c != 0) {
        r = b % c;
        b = c;
        c = r;
    }
    return b;
}