#include <iostream>
#include <fstream>
#include <cstdio>
using namespace std;
ofstream g("fractii.out");
int N, i, j, a, b, R;
long long k;
int main()
{
    freopen ("fractii.in", "r", stdin);
    scanf("%d", &N);
     k=4*N-5;
     for(i=2; i<=N; i++)
       for(j=i+2; j<=N; j++)
        {

           a=i;
           b=j;
           R=a%b;
           while(R!=0)
           {
               a=b;
               b=R;
               R=a%b;
           }
           if(b==1) k+=2;
    g<<k;
    return 0;
}