#include <iostream>
#include <fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int N,a,b,c,x,y,p;
int main()
{
    f>>N;
    a=1;
    b=1;
    c=0;
    while(a<=N)
    {
        x=a;
        y=b;
        while(y!=0)
        {
            p=x%y;
            x=y;
            y=p;
        }
        if(x==1)
            c++;
            b++;
            if(b>N)
            {
                a++;
                b=1;
            }
    }
    g<<c;
    return 0;
}