#include <vector>
#include <stack>
#include <queue>
#include <list>
#include <bitset>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <algorithm>
#include <numeric>
#include <iostream>
#include <iomanip>
#include <string>
#include <chrono>
#include <random>
#include <cmath>
#include <cassert>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <functional>
#include <sstream>

using namespace std;


int main(int argc, char** argv) {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin >> n;
    long long sum = 0;
    for (int i = 1; i <= n; ++i) {
        int x = i;
        if (x % 3 != 0 && x % 5 != 0) {
            sum += x;
        }
    }

    cout << sum << "\n";

    return 0;
}