#include<fstream>
using namespace std;

bool ireductibil(int a,int b)
    {
        bool prime=1;
        int mic=0;
        if (a<b) mic=a; else mic=b;
        for (int x=2;x<=mic;x++)
            if (a%x==0 && b%x==0) {prime=0; break;}
        return prime;
    }

int main()
{
    ifstream f("fractii.in");
    ofstream g("fractii.out");
    int n,fractii=0;
    f>>n;
    for (int i=2;i<=n;i++)
        for (int j=i+1;j<=n;j++)
    {
        bool ireduct=ireductibil(i,j);
        if (ireduct == 1) fractii+=2;
    }
    g<<fractii+n*2-1;
}