#include<fstream>
using namespace std;
ifstream in("fractii.in");
ofstream out("fractii.out");
int main()
{
    int n,total=0,i,j,k;
    in>>n;
    int nrdiv=0;
    for(i=2;i<=n;i++)
    {
        for(j=2*i;j<=n;j++)
        {
            int mic;
            if(i<j)mic=i;
            else mic=j;
            {for(k=2;k<=mic;k++)
            if(i%k==0&&j%k==0) nrdiv++;}
            if(nrdiv==0)total++;
        }
    }
    out<<total;
}