#include <iostream.h>
#include<fstream.h>

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

long n;

void citire()
{
     f>>n;
     f.close();
}

inline int cmmdc(int a, int b)
{
    int r;
    while (b)
    {
          r=a%b;
          a=b;
          b=r;
          }
          if(a>1) return a;
          else return 0;
}

inline int suma()
{
       long long k=0;
     long i,j;
     for(i=2; i<=n;i++)
     for(j=2;j<=n;j++)
     if(cmmdc(i,j)==0) k++;
     return k;
}  

main ()
{    citire();
     g<<(suma()+2*n-1);
g.close();

}