#include <fstream>

using namespace std;

int lnko(unsigned long a,unsigned long b);

int main()
{
	unsigned long n,i,j,sum = 0;
	ifstream f("fractii.in");
	ofstream g("fractii.out");
	f>>n;
	f.close ();
	
	for (i=1;i<n;i++)
		for (j=i+1;j<=n;j++)
			if ( lnko(i,j) == 1 )
				sum ++;
	
	g<<sum*2+1;
	
	g.close();
	
	return 0;
}

int lnko(unsigned long a,unsigned long b)
{
	if (!b) return a;
	return lnko(b, a % b);
}