#include<iostream>;
#include <fstream>;

using namespace std;

ifstream f("fractii.in");
ofstream g("fractii.out");

int main()
{
	int n,m=0;

	f >> n;
	m = 2 * n - 1;
	for (int i = 1; i <= n; i++)
	
		
		for (int j = 1; j <= n; j++)
		{
			
				for (int k = 2; k <= j; k++)
					if ((i / k) != 0 || (j / k) != 0)
						m++;
			
		}

	
	
	g << m;
	f.close();
	g.close();
	return 0;


}