#include<iostream>
#include<fstream>
using namespace std;
int main()
{
	//file declarations
	ifstream f("fractii.in");
	ofstream g("fractii.out");

	//variable declarations
	int number, counter = 0;
	f >> number;
	cout << number;
	if (number == 1)
		counter = 1;
	else
	{
		counter = number;
		for (int i = 2; i <= number; i++)
		{
			counter++;
			for (int j = 1; j <= number; j++)
			{
				if (!(i%j == 0 || j%i == 0))
					counter++;
			}
		}
	}
	g << counter;
	f.close();
	g.close();
	return 0;
}