#include<fstream>
using namespace std;
int s;
int main ()
{
	int n,i,j;
	ifstream is("fractii.in");
	ofstream os("fractii.out");
	is>>n;
	s+=n;
	for (i=2;i<=n;++i)
	{
		for (j=1;j<=n;++j)
		{
			if (j==1)
			{
				++s;
			}
			if (i%j!=0 && j%i!=0)
			{
				++s;
			}
		}
	}
	os<<s<<"\n";
	return 0;
}