#include <algorithm>
#include <cmath>
#include <iostream>
#include <iterator>
#include <map>
#include <queue>
#include <unordered_map>
#include <vector>

using namespace std;

#define ll long long
#define el '\n'
#define rep(i, a, b) for (int i = a; i < b; i++)
#define repi(i, a, b) for (int i = a; i >= b; i--)
#define VI vector<int>
#define VII vector<pair<int, int>>
#define PII pair<int, int>
#define MP make_pair
// #define log(fmt, ...) printf(fmt, ##__VA_ARGS__)
#define log(fmt, ...)
// #define check(...) assert(##__VA_ARGS__)
#define check(...)

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;
    ll ans = 0;
    rep(i, 1, n + 1) {
        if (i % 3 == 0 || i % 5 == 0) {
            continue;
        }
        log("%d ", i);
        ans += (ll)i;
    }
    cout << ans;
}
