#include <fstream>
using namespace std;

int cmmdc ( int a , int b )
{
    if (a==b) return a;

    if (a>b)  return cmmdc ( a-b , b);
        else return cmmdc ( a , b-a);
}

main (){

int n;

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

in >> n;

int suma=2*n-1;

for (int i = 2 ; i <= n ; ++i)
    for (int j = 2 ; j <= n ; ++j)
    if (cmmdc (i,j) == 1)
    suma++;

out << suma;

in.close();
out.close();

}