#include <bits/stdc++.h>
using namespace std;
#define int long long int
#define pb push_back
#define vec vector<int>
#define fo(i, n) for (int i = 0; i < n; i++)
#define foo(i, a, b) for (int i = a; i < b; i++)
#define mp make_pair
#define deb(x) cout << #x << " --> " << x << endl;

#define deb1a(v)                  \
    cout << #v << "--->" << endl; \
    for (auto it : v)             \
    {                             \
        cout << it << " ";        \
    }                             \
    cout << endl;
#define deb2a(v)                  \
    cout << #v << "--->" << endl; \
    for (auto it : v)             \
    {                             \
        for (auto it1 : it)       \
        {                         \
            cout << it1 << " ";   \
        }                         \
        cout << endl;             \
    }

#define mod 1000000007
#define so(v) sort(v.begin(),v.end())
#define fi first
#define se second
//#define endl "\n"
int power(int x, unsigned int y, int p){ int res = 1;x = x % p;while (y > 0)  { if (y & 1)res = (res*x) % p;y = y>>1;  x = (x*x)% p;} return res;}
int mI(int a, int m)  {return power(a, m - 2, m);}


int32_t main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int t;
    t = 1;
    //cin>>t;
    while(t--){
        int n;
        cin>>n;
       int ans=0;
       foo(i,1,n+1){
           if(i%5!=0&&i%3!=0){
               ans+=i;
           }
       }
       cout << ans;
    }
}
