#include <fstream>

using namespace std;

ifstream in("fractii.in");
ofstream out("fractii.out");

long long  k;

int main()
{
    long long n,i,j,k2,k3;

    in>>n;

    k3=n*n;

    i=2;
    while(i<=n)
    {

        j=2;
        while(j<=n)
        {
            if(i%j==0 || j%i==0) k++;
            j++;
        }
        i++;
    }

    k2=k3-k;

    out<<k2;



    return 0;
}