#include <iostream>
#include <fstream>
using namespace std;
int n,a,b,r,suma;
int main()
{
    ifstream fin("fractii.in");
    ofstream fout("fractii.out");
    fin >>n;

    for(int i=2;i<n;i++)
        for(int j=i+1;j<=n;j++)
            {


                   a=i;b=j;
                   r = a % b;
                while(r != 0)
                {
                    a = b;
                    b = r;
                    r = a % b;
                }

                if(b==1)
                    suma++;
            }

    suma*=2;
    suma+=n+n-1;
    fout<<suma;



    return 0;
}