#include<fstream.h>
void euclid(unsigned long a, unsigned long b, unsigned long &d)
{
    if (b == 0) {
        d = a;
    } else
        euclid(b, a % b, d);
}
int main(){
    ifstream f("fractii.in");
    ofstream g("fractii.out");
    
    unsigned long n,i,j,k,d;
    
    f>>n;
    k=2*n-1;
    if(k>=2)
    for(i=2;i<=n;i++)
      for(j=i+1;j<=n;j++)
        {euclid(j,i%j,d);
         if(d==1) k+=2;
          }
    
    g<<k;
    f.close();
    g.close();
    return 0;
}