#include <fstream>

using namespace std;

ifstream fin("fractii.in");

int n;

int main()
{
    fin >> n;

    fin.close();

    int ct = n;

    for(int p =2; p < n; p++)
    {
        for(int q = 1; q<= n; q++)
        {
            if(p%q==0 || q%p==0)
                ct++;
        }
    }


    ofstream fout("fractii.out");
    fout<<ct;
    fout.close();
    return 0;
}