#include<stdio.h>
inline int verif(int i, int j)
{
 if (i%j==0 || j%i==0) return 0;
 return 1;
}

int main()
{
 int n=0, fr=0;
 freopen("fractii.in","r",stdin),
 freopen("fractii.out", "w", stdout);
 scanf("%d", &n);
 fr = (n*2)-1;
 for (int i=2;i<=n;i++)
 {
  for (int j=2;j<=n;j++)
   if (verif(i,j))  fr++;
 }
 printf("%d", fr);

 return 0;
}