#include <iostream>
#include <fstream>

using namespace std;

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

int prime(long a, long b)
{
         long r;
         r=a%b;
         while(r>0)
         {
                   a=b;
                   b=r;
                   r=a%b;
         }

         if (b==1)
         return 1;
         else
         return 0;
}

int main()
{long n,p,q,cont=1;

f>>n;

for (q=1; q<=n; q++)
        for(p=1; p<q; p++)
        if (prime(p,q)==1)
        cont=cont+2;

g<<cont;

f.close();
g.close();

}