#include <iostream>
#include <fstream>

using namespace std;

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

int n;

int cmmdc(int a, int b)
{
  if (!b)
    return a;
  return cmmdc(b, a % b);
}

int main()
{
  fin >> n;
  fin.close();

  if (n < 1 || n > 1000000)
  {
    return 0;
  }

  int count = 0;

  for (int i = 1; i <= n; i++)
  {
    int f = 1;
    while (f <= n)
    {
      if (cmmdc(i, f) == 1)
      {
        count++;
      }
      f++;
    }
  }

  fout << count << endl;
  fout.close();

  return 0;
}