#include<fstream>
bool cmmdc(unsigned long long i, unsigned long long j)
{
	if (!i)return j == 1;
	if (!j)return i == 1;
	return cmmdc(j, i%j);
}
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 * (cmmdc(i, j)); 
	g << 2 * n + nr - 1;
	g.close();
}