#include <fstream.h>
#include <iostream.h>
int main()
{
   ifstream fin("fractii.in");
   ofstream fout("fractii.out");
   long i,j,n,d,ct=0,ctd;
   fin>>n;
   for (i=n;i>=1;i--)
    for (j=1;j<i;j++)
    {
      ctd=1;d=3;
      if (i%j==0) ctd=0;
      if (j%2==0 && i%2==0) ctd=0;
      while (ctd==1 && d<=j)
      {
	if (j%d==0)
	 if (i%d==0) ctd=0;
	d=d+2;
      }
      if (j==1) ctd=1;
      if (ctd==1) ct=ct+2;
     }
  fout<<ct+1;
  return 0;
}