#include <fstream>

using namespace std;

ifstream cin ("fractii.in");
ofstream cout("fractii.out");

int main()
{
    int n,nr,i,j,a,b,c;
    cin>>n;
    nr=n;
    for (i=2;i<=n;i++)
    {
        for (j=1;j<=n;j++)
            if (j==1)
                nr++;
            else if (j==i+1 or j==i-1)
                nr++;
            else
            {
                a=i;
                b=j;
                while (b!=0)
                {
                    c=a%b;
                    a=b;
                    b=c;
                }
                if (a==1)
                    nr++;
            }
    }
    cout<<nr;
    return 0;
}