#include <iostream>
#include <fstream>
#include <cmath>

using namespace std;

int cmmdc(int a, int b) {
    if(a < b)
        swap(a, b);
    int r = a % b;
    while (r != 0) {
        a = b;
        b = r;
        r = a % b;
    }
    return b;
}

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

    int N;
    fin >> N;

    unsigned long long int nrfrac = N + N - 1;
    for (int i = 2; i <= N; i++) {
        for (int j = 2; j <= N; j++) {
            if (cmmdc(i, j) == 1)
                nrfrac++;
        }
    }

    fout << nrfrac;
    return 0;
}