# include <iostream.h>
# include <fstream.h>
using namespace std;
int main()
{
    int r,n,p,q,c=0;
    ifstream f("fractii.in");
    ofstream g("fractii.out");
    f>>n;
    f.close(); 
    for (p=1;p<=n;p++)
    for (q=1;q<=n;q++)
    while (p%q!=0) {   
            r=p%q;
            p=q;
            q=r;}
            if (q==1) c++; 
                       
    g<<c;
    g.close();
    return 0;
}