#include<stdio.h>
#include<math.h>
long int n,p[50000],i,num,d,v,j,k;
void ciur()
{
    d=2;
  while (d<=n)
  {
   for (i=d+d; i<=n; i=i+d) p[i]=1;
   d++;
   while (p[d]==1) d++;
  }
}
main()
{
  freopen("fractii.in","r",stdin);
  freopen("fractii.out","w",stdout);
  scanf("%ld",&n);
  ciur();
  num=n+n-1;
  for (i=2; i<=n; i++)
  {
    for (j=2; j<=n; j++)
    {
      if (i<j)
	  if (j%i!=0)
	      if (p[i]==0) num++;
	      else
	      {v=1;
	      for (k=2; k<=sqrt(n); k++)
		  if ((p[k]==0)&&(i%k==0)&&(j%k==0)){v=0; break;}
	      if (v==1) num++;
	      }
	    else;
	else
	    if (i>j)
		if (i%j!=0)
		    if (p[j]==0) num++;
		    else
		    {
		      v=1;
		      for (k=2; k<=sqrt(n); k++)
			  if ((p[k]==0)&&(i%k==0)&&(j%k==0)) {v=0; break;}
			  if (v==1) num++;
		    }
    }
  }
  printf("%ld",num);
}