#include<fstream>
bool prime(unsigned long long p, unsigned long long o)
{
	for (unsigned long long k = 2; k <= p/2;k++)
	if (!(p%k) && !(o%k))return false;
	return o%p;

}
int main()
{
	unsigned long long n, nr = 0;
	std::ifstream f("fractii.in");
    std::ofstream g("fractii.out");
    f >> n;
    f.close();
	for (unsigned long long i = 2; i < n; i++)
	for (unsigned long long j = i + 1; j <= n; j++)
	    nr += 2 * (prime(i, j)); 
	g << 2 * n + nr - 1;
	g.close();
}