#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int main()
{
    constexpr int FizzBuzz_Z = 4;
    constexpr int Fizz_or_Buzz_Z = 2;
    
    ll r {};
    ll n {};
    cin >> n;

    for( ll i=n ; i>0 ; --i ) {
        if( i % 15 == 0 ) {
            r += FizzBuzz_Z;
        }
        else if( i % 3 == 0 || i % 5 == 0 ) {
            r += Fizz_or_Buzz_Z;
        }
    }

    cout << r << endl;
}