#include <fstream>
#include<iostream>
using namespace std;
int main()
{
    ifstream in;in.open("fractii.in");
    ofstream ou;ou.open("fractii.out",ofstream::out);
    int n,c=0,flag=0;
    in>>n;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++)
         if(j==1 || i%j!=0)flag=flag+1;
    ou<<flag;
    in.close();ou.close();
    return 0;
}