#include <iostream>
#include <fstream>
#include <stdio.h>
#include <algorithm>

using namespace std;

int main(){
    ios::sync_with_stdio(false);
    freopen("fractii.in", "r", stdin);
    freopen("fractii.out", "w", stdout);
    long int n; cin >> n;
    long long int sum = n;
    for(int i = 2; i <= n; i++){
        sum += 1;
        for(int j = 2; j <= n; j++){
            if(__gcd(i, j) == 1) sum++;
        }
    }
    cout << sum;
}