#include <iostream>
#include <fstream>
using namespace std;
int cmmdc(int a, int b){
     int c;
    while (b) {
        c = a % b;
        a = b;
        b = c;
    }
    return a;



}
int main()
{
  int n,i,j,k,nr=0, sum=0;
  ifstream f("fractii.in");
  f>>n;
  f.close();
  ofstream g("fractii.out");
  sum=sum+n+n-1;
  for(i=2; i<n; i++)
  for(j=3; j<=n; j++){
    k=cmmdc(i,j);
    if(k==1)
        nr+=2;
  }

  sum=sum+nr;
  g<<sum<<endl;




    return 0;
}