#include <iostream>
#include <cmath>
#include <fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int v[2],n,i,j,s,d,m,k,a,b,c,nr,P,Q;
double N;
int main()
{
    f>>N;
    for (P=2;P<=N;P++)
     {for (Q=1;Q<=N;Q++)
     {  a=P; b=Q; if (Q>a) {a=Q; b=P;}
        if (a%b!=0) nr++;}}
    nr=nr+2*N-1;
    g<<nr;
    f.close(); g.close();
    return 0;

    }