#include <bits/stdc++.h>
using namespace std;

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

bool prime_intre_ele(int a, int b) {
    while(a != b) {
        if(a > b)
            a = a - b;
        else
            b = b - a;
    }
    
    return a == 1;
}

int main() {
    int n, sol = n;
    fin >> n;
    sol = 1;
    for(int i = 2; i <= n; i++) {
        int nr = 0;
        for(int j = 1; j < i; j++) {
            if(prime_intre_ele(i, j))
                nr++;
        }
        sol += nr * 2;
    }
    fout << sol;
}