#include<iostream>
#include<fstream>
using namespace std;
ifstream f("fractii.in");
ofstream o("fractii.out");
int n,i,j,k,p,q,a,c;
bool ok;
int main()
{
 f>>n;c=0;
 p=1;
 q=1;
 while(p<=n)
 {
 if(p>q) a=q;
    else a=p;
  ok=1;
  for(k=2;k<=a;k++)
    if(p%k==0&&q%k==0) {ok=0;break;}
  if(ok==1) c++;
  if(q<n) q++;
     else {p++;q=1;}
  }
   o<<c;
}