#include<fstream>
using namespace std;
int cmmdc(int a, int b)
{
	int x;
	if (a<b)
	{
		x=a;
		a=b;
		b=x;
	}
	while (b != 0)
	{
		a = a%b;
		x=a;
		a=b;
		b=x;
	}
	return (a);
}

int fi(int n)
{
	int d=0;
	for (int i=1; i<=n; i++)
	{
		if ( (cmmdc (i, n)) == 1)
		{
			d=d+1;
		}
	}
	return (d);
}
int main()
{
	ifstream fin("fractii.in");
	ofstream fout("fractii.out");
	int g, p;
	fin>>g;
	p=0;
	for (int l=1; l<=g; l++)
	{
		//fout << fi(l) << "\n";
		p = p + fi (l);
	}
	p = (p-1)*2+1;
	fout<<p;
	return 0;
}