#include <iostream>
#include <fstream>
using namespace std;

int N, count = 1;

int cmmdc(int, int);

int main()
{
    int i, j;

	ifstream fin("fractii.in");
	ofstream fout("fractii.out");

	fin >> N;
	fin.close();

	for(i = 1; i < N; i++)
        for(j = i + 1; j <= N; j++)
            if(cmmdc(i ,j) == 1)
                count += 2;

	fout << count;
	fout.close();

	return 0;
}


int cmmdc(int a, int b)
{
	int r = a % b;

	while (r) {
		a = b;
		b = r;
		r = a % b;
	}

	return b;
}