#include <fstream>
using namespace std;

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

    int n,a,b,x;
    bool e=false;

    fin >> n;
    int s=1,p=0;

    for(int i=1;i<n;i++)
    for(int j=i+1;j<=n;j++){
            a=i;b=j;
        while (b)
        {
          x = a % b;
          a = b;
          b = x;
        }
      if(a==1)p++;
    }
    fout << s+p*2;
	return 0;
}