#include <iostream>
#include <fstream>
using namespace std;
unsigned nr, n, i, j;

ifstream fin("fractii.in");
ofstream fout("fractii.out");

unsigned ired (unsigned x, unsigned y)
{unsigned ok=1,i;
   
   i=2;
  while(i<=x && ok!=0)
  {if(y%i==0 && x%i==0)
  ok=0;
  i++;
  }
  return ok;
}
 
 int main()
{
    fin >> n;
    nr=n*(n-1)+1;
 	for(i=2; i<=n; i++)
	for(j=i+1; j<=n; j++)
	{if (!ired(i,j) )
	{
	 nr-=2;
	 }
	}
fout<< nr;
 }