// #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
// #include <atcoder/all>
using namespace std;
// using namespace atcoder;

#define int long long
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define rep(i, n) for (int i = 0; i < n; ++i)
#define REP(i, n) for (int i = 0; i < n; ++i)
#define range(i,a,b) ((a)<=(i) && (i)<(b))
#define debug(x) cout << #x << " = " << (x) << endl;
#define fs first
#define sc second
#define pb push_back
#define eb emplace_back
#define SP << " " <<

typedef long long ll;
typedef pair<int, int> P;
typedef tuple<int, int, int> T;
typedef vector<int> vec;
typedef vector<P> pvec;
typedef vector<vector<int>> vvec;
typedef vector<vector<P>> pvvec;
typedef priority_queue<int> PQI;
typedef priority_queue<P> PQP;
typedef priority_queue<int,vector<int>,greater<int>> PQIG;
typedef priority_queue<P,vector<P>,greater<P>> PQPG;

const vector<int> DX = {0, -1, 0, 1, 1, 1, -1, -1};
const vector<int> DY = {1, 0, -1, 0, 1, -1, 1, -1};
constexpr int MOD = (1000000007);
// const int MOD = (998244353);
// const int INF = (1 << 30); // 1073741824
const ll INF = (1LL << 60); // 1152921504606846976
const double PI = (3.141592653589794);
const double EPS = (0.0000000001); // 10^(-10)

template<class T> inline bool chmin(T& a, T b) {if (a > b) {a = b; return 1;} return 0;}
template<class T> inline bool chmax(T& a, T b) {if (a < b) {a = b; return 1;} return 0;}
template<class T> inline T ceil(T a, T b) {return T((a + b - 1) / b);}
template<class T> inline T round(T a, T b) {return T(a / b);}
template< typename T1, typename T2 > istream &operator>>(istream &is, pair< T1, T2 > &p) { is >> p.first >> p.second; return is; }
template <class T> inline void out(T &a) { bool flag=true; for(auto&x:a){if(flag) {flag=false;} else{ cout << ' '; } cout<<x; } cout << endl; }



//----------------------------------------------------------------
int nmax=200000; // 2*(10^5)
vvec G(nmax);


template <ll mod>
struct modint
{
  ll val = 0;
  //コンストラクタ
  modint(ll x = 0)
  {
    while (x < 0)
      x += mod;
    val = x % mod;
  }
  //コピーコンストラクタ
  modint(const modint &r) { val = r.val; }
  //算術演算子
  modint operator-() { return modint(-val); } //単項
  modint operator+(const modint &r) { return modint(*this) += r; }
  modint operator-(const modint &r) { return modint(*this) -= r; }
  modint operator*(const modint &r) { return modint(*this) *= r; }
  modint operator/(const modint &r) { return modint(*this) /= r; }
  //代入演算子
  modint &operator+=(const modint &r)
  {
    val += r.val;
    if (val >= mod)
      val -= mod;
    return *this;
  }
  modint &operator-=(const modint &r)
  {
    if (val < r.val)
      val += mod;
    val -= r.val;
    return *this;
  }
  modint &operator*=(const modint &r)
  {
    val = val * r.val % mod;
    return *this;
  }
  modint &operator/=(const modint &r)
  {
    ll a = r.val, b = mod, u = 1, v = 0;
    while (b)
    {
      ll t = a / b;
      a -= t * b;
      swap(a, b);
      u -= t * v;
      swap(u, v);
    }
    val = val * u % mod;
    if (val < 0)
      val += mod;
    return *this;
  }
  //等価比較演算子
  bool operator==(const modint &r) { return this->val == r.val; }
  bool operator!=(const modint &r) { return this->val != r.val; }
  bool operator<(const modint &r) { return this->val < r.val; }
  bool operator>(const modint &r) { return this->val > r.val; }
  bool operator<=(const modint &r) { return this->val <= r.val; }
  bool operator>=(const modint &r) { return this->val >= r.val; }
  friend constexpr istream &operator>>(istream &is, modint &x)
  {
    ll t;
    is >> t;
    x = t;
    return (is);
  }
  friend constexpr ostream &operator<<(ostream &os, const modint &x)
  {
    return os << x.val;
  }
  int getMod() { return mod; }
  modint<mod> modpow(const modint<mod> &a, long long n)
  {
    if (n == 0)
      return 1;
    auto t = modpow(a, n / 2);
    t = t * t;
    if (n & 1)
      t = t * a;
    return t;
  }
};
using mint = modint<MOD>;
using mvec = vector<mint>;
using mvvec = vector<vector<mint>>;

// 二項係数ライブラリ
template <class T>
struct BC
{
  vector<T> fact_, inv_, finv_;
  constexpr BC() {}
  constexpr BC(int n) noexcept : fact_(n, 1), inv_(n, 1), finv_(n, 1)
  {
    init(n);
  }
  constexpr void init(int n) noexcept
  {
    fact_.assign(n, 1);
    inv_.assign(n, 1);
    finv_.assign(n, 1);
    for (int i = 2; i < n; i++)
    {
      fact_[i] = fact_[i - 1] * i;
      inv_[i] = -inv_[MOD % i] * (MOD / i);
      finv_[i] = finv_[i - 1] * inv_[i];
    }
  }
  constexpr T C(int n, int k) const noexcept
  {
    if (n < k || n < 0 || k < 0)
      return 0;
    return fact_[n] * finv_[k] * finv_[n - k];
  }
  constexpr T P(int n, int k) const noexcept
  {
    if (n < k || n < 0 || k < 0)
      return 0;
    return fact_[n] * finv_[n - k];
  }
  constexpr T H(int n, int k) const noexcept
  {
    return C(n + k - 1, k);
  }
  constexpr T fact(int n) const noexcept
  {
    if (n < 0)
      return 0;
    return fact_[n];
  }
  constexpr T inv(int n) const noexcept
  {
    if (n < 0)
      return 0;
    return inv_[n];
  }
  constexpr T finv(int n) const noexcept
  {
    if (n < 0)
      return 0;
    return finv_[n];
  }
};
BC<mint> bc(100000);

int gcd(int x, int y) { return y ? gcd(y, x%y) : x; }
int lcm(int x, int y) { return x/gcd(x, y)*y; }
int mod_pow(int x, int y) { int res = 1; while (y > 0) { if (y & 1) { res = res * x % MOD; } x = x * x % MOD; y >>= 1; } return res; }
int cmb(int n,int k){ if(n<k){ return 0;} int res=1,nn=n,kk=1;k=min(k,n-k); for(int i=0;i<k;i++){ res*=nn-i;res/=kk+i;} return res; }
ll comb(ll n,ll k){ ll res=1; for(int i=0;i<k;i++){ (res*=(n-i)%MOD)%=MOD; } for(int i=1;i<=k;i++){ (res*=mod_pow(i,MOD-2))%=MOD; } return res; }
int to_int(string s) { int n = s.size(); int ans = 0; for (int i = 0; i < n; i++) { ans = ((ans * 10) + (s[i] - '0')) % MOD; } return ans; }
int DigitSum(int x){ int ret=0; while(x){ ret++;x/=10;} return ret; }
bool is_prime(int n) { for(int i = 2; i*i <= n; i++) { if (n % i == 0) return false; } return n != 1; }
int extgcd(int a, int b, int& x, int& y) { // ax+by = gcd(a,b) >> gcd(a,b)
  int d = a;
  if(d != 0) { d = extgcd(b, a%b, y, x); y -= (a/b)*x; }
  else { x = 1, y = 0; }
  return 0;
}
void solve4ts()
{
  
  
  int s;
  cin>>s;
  mint ans=0;
  for(int x=1;x<2200;x++){
    int nokori=s-3*x;
    if(nokori<0) continue;
    ans+=comb(nokori+x-1,x-1);
    // cout<<x<<" "<<comb(nokori+x,x-1)<<endl;
  }
  cout<<ans<<endl;
  
}
//-----------------------------------------------------------------

signed main(){ ios::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(15);
  int repeat = 1;
  // cin >> repeat;
  while(repeat--) solve4ts();
}

/*

g++ -std=c++1z code.cpp

./a.out

python3 expander.py code.cpp

*/

Measured memory_bytes: 10164