#include <iostream>
#include <fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int n,p,q,cnt;
void citire()
{
    f>>n;
}
int ireductibil(int x,int y)
{
    if(x%y==0||y%x==0)return 0;
    else return 1;
}
void generare()
{
    for(p=2;p<=n;p++)
        for(q=2;q<=n;q++) if(ireductibil(p,q)==1) cnt++;
        cout<<cnt;
}
int main()
{
 citire();
    cnt=n+(n-1);
    generare();
}