#pragma region kyopro_template
#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define each(x, v) for (auto &x : v)
#define all(v) (v).begin(), (v).end()
#define sz(v) ((int)(v).size())
#define mem(a, val) memset(a, val, sizeof(a))
#define ini(...)   \
  int __VA_ARGS__; \
  in(__VA_ARGS__)
#define inl(...)         \
  long long __VA_ARGS__; \
  in(__VA_ARGS__)
#define ins(...)      \
  string __VA_ARGS__; \
  in(__VA_ARGS__)
#define inc(...)    \
  char __VA_ARGS__; \
  in(__VA_ARGS__)
#define in2(s, t)                           \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i]);                         \
  }
#define in3(s, t, u)                        \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i], u[i]);                   \
  }
#define in4(s, t, u, v)                     \
  for (int i = 0; i < (int)s.size(); i++) { \
    in(s[i], t[i], u[i], v[i]);             \
  }
#define rep(i, N) for (long long i = 0; i < (long long)(N); i++)
#define repr(i, N) for (long long i = (long long)(N)-1; i >= 0; i--)
#define rep1(i, N) for (long long i = 1; i <= (long long)(N); i++)
#define repr1(i, N) for (long long i = (N); (long long)(i) > 0; i--)
using namespace std;
void solve();
using ll = long long;
template <class T = ll>
using V = vector<T>;
using vi = vector<int>;
using vl = vector<long long>;
using vvi = vector<vector<int>>;
using vd = V<double>;
using vs = V<string>;
using vvl = vector<vector<long long>>;
using P = pair<long long, long long>;
using vp = vector<P>;
using pii = pair<int, int>;
using vpi = vector<pair<int, int>>;
constexpr int inf = 1001001001;
constexpr long long infLL = (1LL << 61) - 1;
template <typename T, typename U>
inline bool amin(T &x, U y) {
  return (y < x) ? (x = y, true) : false;
}
template <typename T, typename U>
inline bool amax(T &x, U y) {
  return (x < y) ? (x = y, true) : false;
}
template <typename T, typename U>
ll ceil(T a, U b) {
  return (a + b - 1) / b;
}
constexpr ll TEN(int n) {
  ll ret = 1, x = 10;
  while (n) {
    if (n & 1) ret *= x;
    x *= x;
    n >>= 1;
  }
  return ret;
}

template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  os << p.first << " " << p.second;
  return os;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
  is >> p.first >> p.second;
  return is;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
  int s = (int)v.size();
  for (int i = 0; i < s; i++) os << (i ? " " : "") << v[i];
  return os;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &v) {
  for (auto &x : v) is >> x;
  return is;
}
void in() {}
template <typename T, class... U>
void in(T &t, U &... u) {
  cin >> t;
  in(u...);
}
void out() { cout << "\n"; }
template <typename T, class... U>
void out(const T &t, const U &... u) {
  cout << t;
  if (sizeof...(u)) cout << " ";
  out(u...);
}
template <typename T>
void die(T x) {
  out(x);
  exit(0);
}

#ifdef NyaanDebug
#include "NyaanDebug.h"
#define trc(...)                   \
  do {                             \
    cerr << #__VA_ARGS__ << " = "; \
    dbg_out(__VA_ARGS__);          \
  } while (0)
#define trca(v, N)       \
  do {                   \
    cerr << #v << " = "; \
    array_out(v, N);     \
  } while (0)
#define trcc(v)                             \
  do {                                      \
    cerr << #v << " = {";                   \
    each(x, v) { cerr << " " << x << ","; } \
    cerr << "}" << endl;                    \
  } while (0)
#else
#define trc(...)
#define trca(...)
#define trcc(...)
int main() { solve(); }
#endif

struct IoSetupNya {
  IoSetupNya() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(15);
    cerr << fixed << setprecision(7);
  }
} iosetupnya;

#pragma endregion
constexpr long long MOD = /**/ 1000000007; //*/ 998244353;

template< int mod >
struct ModInt {
  int x;

  ModInt() : x(0) {}

  ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {}

  ModInt &operator+=(const ModInt &p) {
    if((x += p.x) >= mod) x -= mod;
    return *this;
  }

  ModInt &operator-=(const ModInt &p) {
    if((x += mod - p.x) >= mod) x -= mod;
    return *this;
  }

  ModInt &operator*=(const ModInt &p) {
    x = (int) (1LL * x * p.x % mod);
    return *this;
  }

  ModInt &operator/=(const ModInt &p) {
    *this *= p.inverse();
    return *this;
  }

  ModInt operator-() const { return ModInt(-x); }

  ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; }

  ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; }

  ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; }

  ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; }

  bool operator==(const ModInt &p) const { return x == p.x; }

  bool operator!=(const ModInt &p) const { return x != p.x; }

  ModInt inverse() const {
    int a = x, b = mod, u = 1, v = 0, t;
    while(b > 0) {
      t = a / b;
      swap(a -= t * b, b);
      swap(u -= t * v, v);
    }
    return ModInt(u);
  }

  ModInt pow(int64_t n) const {
    ModInt ret(1), mul(x);
    while(n > 0) {
      if(n & 1) ret *= mul;
      mul *= mul;
      n >>= 1;
    }
    return ret;
  }

  friend ostream &operator<<(ostream &os, const ModInt &p) {
    return os << p.x;
  }

  friend istream &operator>>(istream &is, ModInt &a) {
    int64_t t;
    is >> t;
    a = ModInt< mod >(t);
    return (is);
  }

  static constexpr int get_mod() { return mod; }
};
using mint = ModInt<MOD>;
using vm = vector<mint>;


struct divisor_transform{
  template <typename T>
  static constexpr void zeta_transform(vector<T> &a){
    int N = a.size() - 1; 
    vector<int> sieve(N + 1, true);
    for(int p = 2; p <= N; p++)
      if(sieve[p])
        for(int k = 1; k * p <= N; ++k)
          sieve[k * p] = false , a[k * p] += a[k];    
  }

  template<typename T>
  static constexpr void mobius_transform(T &a){
    int N = a.size() - 1; 
    vector<int> sieve(N + 1, true);
    for(int p = 2; p <= N; p++)
      if(sieve[p])
        for(int k = N / p; k > 0; --k)
          sieve[k * p] = false , a[k * p] -= a[k];    
  }
  
  // verify 
  // https://atcoder.jp/contests/arc064/submissions/7707249
  template<typename T>
  static constexpr void zeta_transform(map<long long, T> &a){
    for(auto &x : a) for(auto &y : a){
      if(x == y) break;
      if(x.first % y.first == 0) x.second += y.second;
    }
  }
  template<typename T>
  static constexpr void mobius_transform(map<long long, T> &a){
    for(auto &x : a) for(auto &y : a){
      if(x == y) break;
      if(x.first % y.first == 0) x.second -= y.second;
    }
  }

};

// verify
// https://atcoder.jp/contests/agc038/submissions/7683063
// https://www.codechef.com/viewsolution/26767783
struct multiple_transform{
  template <typename T>
  static constexpr void zeta_transform(vector<T> &a){
    int N = a.size() - 1;
    vector<int> sieve(N + 1, true);
    for(int p = 2; p <= N; ++p)
      if(sieve[p])
        for(int k = N / p; k > 0; --k)
          sieve[k * p] = false , a[k] += a[k * p];
  }
  template <typename T>
  static constexpr void mobius_transform(vector<T> &a){
    int N = a.size() - 1;
    vector<int> sieve(N + 1, true);
    for(int p = 2; p <= N; ++p)
      if(sieve[p])
        for(int k = 1; k * p <= N; ++k)
          sieve[k * p] = false , a[k] -= a[k * p];
  }

  template<typename T>
  static constexpr void zeta_transform(map<long long, T> &a){
    for(auto it=a.rbegin(); it!=a.rend(); it++)
      for(auto it2=a.rbegin(); it2!=it; it2++)
        if(it2->first % it->first == 0)
          it->second += it2->second;
  }
  template<typename T>
  static constexpr void mobius_transform(map<long long, T> &a){
    for(auto it=a.rbegin(); it!=a.rend(); it++)
      for(auto it2=a.rbegin(); it2!=it; it2++)
        if(it2->first % it->first == 0)
          it->second -= it2->second;
  }

};

template<typename T>
static constexpr vector<T> mobius_function(int N){
  vector<T> a(N + 1 , 0);
  a[1] = 1;
  divisor_transform::mobius_transform(a);
  return a;
}

template<int N>
struct constexpr_mobius_function{
  int mobius[N + 1] , sieve[N + 1];
  constexpr constexpr_mobius_function(): mobius() , sieve(){
    for(int i=1; i<=N; i++) sieve[i] = 1, mobius[i] = 0;
    mobius[1] = 1;
    for(int p = 2; p <= N; p++)
      if(sieve[p])
        for(int k = N / p; k > 0; --k)
          sieve[k * p] = false , mobius[k * p] -= mobius[k];    
  }
  const int& operator[](int i)const{return mobius[i];}
};

// N = 1000000 , pnum = 78498
template<int N,int pnum> struct constexpr_prime{
  int prime[pnum];
  int sieve[N + 1];
  constexpr_prime() : prime() , sieve() {
    for(int i=2;i<=N;i++) sieve[i]=1;
    int idx = 0;
    for(long long p = 2; p <= N; p++){
      if(sieve[p]){
        prime[idx++] = p;
        for(long long j = p * p; j <= N; j += p) sieve[j] = 0;
      }
    }
  }
  const long long& operator[](long long i) const{return prime[i];}
};

// verify
template<typename T,typename F>
static constexpr unordered_map<long long,T> divisor_zeta_transform(long long N, F f){
  // factorization
  unordered_map<long long,long long> factors;
  {
    long long M = N;
    for(long long i = 2; i * i <= M; i++)
      while(M % i == 0) factors[i]++ , M /= i;
    if(M != 1) factors[M]++;
  }
  unordered_map<long long,T> ret;
  ret.emplace(1 , 1);
  for(auto &d : factors){
    auto ret2 = ret;
    T prev = 1;
    for(long long i = 1 , cur = d.first; 
      i <= d.second;
      i++ , cur *= d.first){
      T val = ( prev += f(cur) );
      for(auto &x : ret) 
        ret2.emplace(x.first*cur , x.second*val);
    }
    swap(ret , ret2);
  }
  return ret;
}

// verify
// https://onlinejudge.u-aizu.ac.jp/status/users/NyaanNyaan/submissions/1/NTL_1_D/judge/3892694/C++14
// https://atcoder.jp/contests/abc020/submissions/7695313
template<typename T,typename F>
static constexpr unordered_map<long long,T> divisor_mobius_transform(long long N, F f){
  // factorization
  unordered_map<long long,long long> factors;
  {
    long long M = N;
    for(long long i = 2; i * i <= M; i++)
      while(M % i == 0) factors[i]++ , M /= i;
    if(M != 1) factors[M]++;
  }
  unordered_map<long long,T> ret;
  ret.emplace(1 , 1);
  for(auto &d : factors){
    auto ret2 = ret;
    for(long long i = 1,cur = d.first , prev = 1; 
      i <= d.second; 
      i++ , cur *= d.first , prev *= d.first){
      T val = f(cur) - f(prev);
      for(auto &x : ret) 
        ret2.emplace(x.first*cur , x.second*val);
    }
    swap(ret , ret2);
  }
  return ret;
}


void solve(){
  ini(K);
  ll ans = 0;
  rep1(i,K){
    if(i%3!=0&&i%5!=0)ans+=i;
  }
  out(ans);
}

Measured memory_bytes: 3608