#include <cstdio>

using namespace std;
int n,i,j,x,y,r,nr,w;
int main()
{
    freopen ("fractii.in","r",stdin);
    freopen ("fractii.out","w",stdout);
    scanf ("%d", &n);
    nr=2*(n-1)+1;
    for (i=2;i<=n;i++)
        for (j=i+1;j<=n;j++)
        {
             x=i;
             y=j;
             r=x%y;
             while (r>0)
             {
                 x=y;
                 y=r;
                 r=x%y;
             }
             if (y==1)
                nr+=2;
        }
    printf ("%d", nr);
    return 0;
}