//#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
#define rep(i, n) for(int i=0; i<n; ++i)
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
using namespace std;
using ll = int64_t;
using ld = long double;
using P = pair<int, int>;
using vs = vector<string>;
using vi = vector<int>;
using vvi = vector<vi>;
template<class T> using PQ = priority_queue<T>;
template<class T> using PQG = priority_queue<T, vector<T>, greater<T> >;
const int INF = 0xccccccc;
const ll LINF = 0xcccccccccccccccLL;
template<typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) {return a < b && (a = b, true);}
template<typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) {return a > b && (a = b, true);}
template<typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) { return is >> p.first >> p.second;}
template<typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) { return os << p.first << ' ' << p.second;}

const unsigned int mod = 1000000007;
//const unsigned int mod = 998244353;

struct mint {
  unsigned int x;
  mint():x(0) {}
  mint(int64_t x_) {
    int64_t v = int64_t(x_ % mod);
    if(v < 0) v += mod;
    x = (unsigned int)v;
  }
  static mint row(int v) {
    mint v_;
    v_.x = v;
    return v_;
  }
  mint operator-() const { return mint(-x);}
  mint& operator+=(const mint a) {
    if ((x += a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator-=(const mint a) {
    if ((x += mod-a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator*=(const mint a) {
    uint64_t z = x;
    z *= a.x;
    x = (unsigned int)(z % mod);
    return *this;
  }
  mint operator+(const mint a) const { return mint(*this) += a;}
  mint operator-(const mint a) const { return mint(*this) -= a;}
  mint operator*(const mint a) const { return mint(*this) *= a;}
  friend bool operator==(const mint &a, const mint &b) {return a.x == b.x;}
  friend bool operator!=(const mint &a, const mint &b) {return a.x != b.x;}
  mint &operator++() {
    x++;
    if(x == mod) x = 0;
    return *this;
  }
  mint &operator--() {
    if(x == 0) x = mod;
    x--;
    return *this;
  }
  mint operator++(int) {
    mint result = *this;
    ++*this;
    return result;
  }
  mint operator--(int) {
    mint result = *this;
    --*this;
    return result;
  }
  mint pow(int64_t t) const {
    mint x_ = *this, r = 1;
    while(t) {
      if(t&1) r *= x_;
      x_ *= x_;
      t >>= 1;
    }
    return r;
  }
  //for prime mod
  mint inv() const { return pow(mod-2);}
  mint& operator/=(const mint a) { return *this *= a.inv();}
  mint operator/(const mint a) {return mint(*this) /= a;}
};

istream& operator>>(istream& is, mint& a) { return is >> a.x;}
ostream& operator<<(ostream& os, const mint& a) { return os << a.x;}

struct combination {
  vector<mint> frac, ifrac;
  combination(int n):frac(n+1), ifrac(n+1) {
    assert(n < mod);
    frac[0] = 1;
    for (int i = 1; i <= n; ++i) frac[i] = frac[i-1]*i;
    ifrac[n] = frac[n].inv();
    for (int i = n; i >= 1; --i) ifrac[i-1] = ifrac[i]*i;
  }
  mint operator()(int n, int k) {
    if (k < 0 || k > n) return 0;
    return frac[n]*ifrac[k]*ifrac[n-k];
  }
} c(1000000);

//head

mint ans;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int s;
  cin >> s;
  if(s < 3) {
    cout << 0 << endl;
    return 0;
  }
  s -= 3;
  int cnt = 0;
  while(s >= 0) {
    ans += c(s+cnt, cnt);
    cnt++;
    s -= 3;
  }
  cout << ans << endl;
}

Measured memory_bytes: 10984