#include <iostream>

int main() {
    uint64_t n;
    std::cin >> n;
    uint64_t z = 0;
    for (uint64_t i = 1; i <= n; ++i) {
        if (i % 15 == 0) {
            z += 4;
        } else if (i % 3 == 0 || i % 5 == 0) {
            z += 2;
        }
    }
    std::cout << z << std::endl;
}