#include<iostream>
#include<fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
long cmmdc (long x, long y)
{
	while (x!=y)
		if (x>y)
			x=x-y;
		else
			y=y-x;
		return x;
}
int main()
{
	long n,i,j,x;
	f>>n;
	x=n;
	for (i=2;i<=n;i++)
		for (j=1;j<=n;j++)
			if (cmmdc(i,j)==1)
				++x;
	g<<x;
}