#include <iostream>
#include <fstream>
#include <algorithm>

using namespace std;

ifstream input("fractii.in");
ofstream output("fractii.out");

int main()
{
    int N, a, b, r, cateisba;
    input >> N;
    cateisba = 2 * N - 1;
    for(int i = 2; i <= N; i++) {
        for(int j = 2; j <= N; j++) {
            if(__gcd(i, j) == 1)
                cateisba++;
        }
    }
    output << cateisba;
    return 0;
}