#include <bits/stdc++.h>
using namespace std;
#define all(x) (x).begin(), (x).end()
#define allr(x) (x).rbegin(), (x).rend()
#define pb push_back
#define ff first
#define ss second
#define ll long long
#define ld long double
#define pll pair<ll,ll>
#define ppll pair<pll,ll>
#define vi vector <ll>
#define out(x) return cout<<x,0;
#define precision(x,d) cout<<fixed<<setprecision(d)<<x
#define f(i,x,n) for(ll i=x;i<n;i++)
#define lc(n) 2*n+1
#define rc(n) 2*n+2
#define fill(a,b) memset((a),(b),sizeof((a)))
#define FAST ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0);srand(time(NULL));
ll power(ll x,ll y,ll m){ll r=1;for(;y;y>>=1){if(y&1)r=r*x%m;x=x*x%m;}return r;} 
const ll N = 1e6 + 5, M = 1e18 + 7; 

int main(){
    FAST;
    ll n, k, t, m = 0, x = 0, i, ans = 0, j, y = 0, z = 4, c = 0;
    cin >> n;
    f(i, 1, n + 1){
        if(i%3 != 0 && i%5 != 0) ans += i;
    }
    cout << ans;
}   