#include <fstream>

using namespace std;

int main()
{int n,contor=0,i,j;
ifstream fin("fractii.in");
fin>>n;
int r,a,b;
ofstream fout("fractii.out");
i=1; j=1;
for(j=1;j<=n;j++)

 {  a=i; b=j;

    while(b>0)
    {
        r=a%b;
        a=b;
        b=r;
    }
            if(a==1) contor++;
    if(j==n) i++;
        }

fout<<contor;

    return 0;
}