#include <iostream>
#include <stdlib.h>

using namespace std;

bool cmmdc( int a , int b )
{
	while ( a != 1 && b != 1 && a != b )
	{
		if (a > b ) a =a-b;
		else b= b-a;
	}
	if ( a == b && a != 1) return true;
	else return false;
}

int main()
{
	FILE *fs = fopen("fractii.in","rt");
	FILE *gs = fopen("fractii.out","wt");
	if (fs == NULL) return -1;
	int nr,i,j,no;
	if (fscanf (fs,"%i",&nr) == 1 )
	{
		no = nr * (nr-1) + 1 ;
		if (nr <=0 ) fprintf(gs,"%i",0);
		else if ( nr == 1) fprintf (gs,"%i",1);
			else {
			for ( i= 1 ; i <= nr ;i++)
				for ( j = 1 ; j<i;j++)
			{
				if (cmmdc (i,j)) 
					no = no - 2;
			}
			  fprintf (gs,"%i",no);
				}
	}
	return 0;
}