#include <fstream>
#include<algorithm>
#include<vector>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
template<class T>
class lafel
{
public:
    bool operator()(T x,T y)
    {
        return x==y;
    }
};

int main()
{unsigned long n;
int k=0;
float p,q;
    f>>n;
    vector<float> s(0);
        for(p=1;p<=n;p++)
    {for(q=1;q<=n;q++)
      s.push_back(p/q);
    }
    vector<float>::iterator it,it1;
    it=unique(s.begin(),s.end(),lafel<int>());
    for(it1=s.begin();it1!=it;++it1)
    {
        k++;
    }
    g<<k;
f.close();
g.close();
    return 0;
}