#include<stdio.h>
#include<string.h>
#define Nmax 1000001
int a[Nmax][Nmax];
long n;
int main()
{
long fr=0,i,k,j;
freopen("fractii.in","r",stdin);
freopen("fractii.out","w",stdout);
scanf("%ld",&n);
long l,m;
for(i=2;i<=n;i++)
   for(j=2;j<=n;j++)
       if(i%j==0)
	  {
	  l=i;m=j;
	  for(k=2;l<=n && m<=n;k++)
		  {
		  a[l][m]=1;
		  a[m][l]=1;
		  m=j*k;
		  l=i*k;
		  }
	  }
for(i=1;i<=n;i++)
   for(j=1;j<=n;j++)
      if(a[i][j]==0)
	 fr++;
printf("%ld\n",fr);
return 0;
}