#include <fstream.h>

ifstream in("fractii.in");
ofstream out("fractii.out");
int n;

int prim(int a, int b)
{
	while ( b )
	{
		int t = b;
		b = a % b;
		a = t;
	}

	return a;
}

int coprim(int x)
{
	int k=0;
	for ( int i = 1; i <= n; ++i )
		if ( x != i )
			if ( prim(x, i) == 1 )
				++k;
	return k;
}

int main()
{
	in >> n;
	int s = 0;
	for ( int i = 1; i <= n; ++i )
		s += coprim(i);

	out << s+1 << endl;

	return 0;
}