#include<iostream>
using namespace std;
int main(){
    long long int n,count=0;
    cin >> n;
    for(int i=1; i<n+1; i++){
        if(i%15==0){
            count+=4;
        }else if(i%5==0 || i%3==0){
            count+=2;
        }
    }
    cout << count << endl;
    return 0;
}