#include <bits/stdc++.h> 

using namespace std;
typedef long long ll;

int main() {
    ll N;
    cin >> N;

    ll count = 0;
    for (int i = 1; i <= N; i++) {
        if (i % 3 == 0 && i % 5 == 0) {
            count += 4;
        } else if (i % 3 == 0) {
            count += 2;
        } else if (i % 5 == 0) {
            count += 2;
        }
    }

    cout << count << endl;
}