#line 1 "main.cpp"

/**
 * @title Template
 */

#include <iostream>
#include <algorithm>
#include <utility>
#include <numeric>
#include <vector>
#include <array>
#include <cassert>

#line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/other/chmin_chmax.cpp"

template <class T, class U>
constexpr bool chmin(T &lhs, const U &rhs) {
  if (lhs > rhs) { lhs = rhs; return true; }
  return false;
}

template <class T, class U>
constexpr bool chmax(T &lhs, const U &rhs) {
  if (lhs < rhs) { lhs = rhs; return true; }
  return false;
}

/**
 * @title Chmin/Chmax
 */
#line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/other/range.cpp"

#line 4 "/Users/kodamankod/Desktop/cpp_programming/Library/other/range.cpp"

class range {
public:
  class iterator {
  private:
    int64_t M_position;

  public:
    constexpr iterator(int64_t position) noexcept: M_position(position) { }
    constexpr void operator ++ () noexcept { ++M_position; }
    constexpr bool operator != (iterator other) const noexcept { return M_position != other.M_position; }
    constexpr int64_t operator * () const noexcept { return M_position; }
  };

  class reverse_iterator {
  private:
    int64_t M_position;
  
  public:
    constexpr reverse_iterator(int64_t position) noexcept: M_position(position) { }
    constexpr void operator ++ () noexcept { --M_position; }
    constexpr bool operator != (reverse_iterator other) const noexcept { return M_position != other.M_position; }
    constexpr int64_t operator * () const noexcept { return M_position; }
  };
  
private:
  const iterator M_first, M_last;

public:
  constexpr range(int64_t first, int64_t last) noexcept: M_first(first), M_last(std::max(first, last)) { }
  constexpr iterator begin() const noexcept { return M_first; }
  constexpr iterator end() const noexcept { return M_last; }
  constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator(*M_last - 1); } 
  constexpr reverse_iterator rend() const noexcept { return reverse_iterator(*M_first - 1); } 
};

/**
 * @title Range
 */
#line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/other/rev.cpp"

#include <type_traits>
#include <iterator>
#line 6 "/Users/kodamankod/Desktop/cpp_programming/Library/other/rev.cpp"

template <class T>
class rev_impl {
public:
  using iterator = decltype(std::rbegin(std::declval<T>()));

private:
  const iterator M_begin;
  const iterator M_end;

public:
  constexpr rev_impl(T &&cont) noexcept: M_begin(std::rbegin(cont)), M_end(std::rend(cont)) { }
  constexpr iterator begin() const noexcept { return M_begin; }
  constexpr iterator end() const noexcept { return M_end; }
};

template <class T>
constexpr decltype(auto) rev(T &&cont) {
  return rev_impl<T>(std::forward<T>(cont));
}

/**
 * @title Reverser
 */
#line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/modular.cpp"

#include <cstdint>
#line 5 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/modular.cpp"

template <uint32_t Mod>
class static_modint {
public:
  using value_type = uint32_t;
  using cover_type = uint64_t;

  template <class T>
  static constexpr value_type normalize(T value_) noexcept {
    if (value_ < 0) {
      value_ = -value_;
      value_ %= Mod;
      if (value_ == 0) return 0;
      return Mod - value_;
    }
    return value_ % Mod;
  }

private:
  value_type value;

public:
  constexpr static_modint() noexcept : value(0) { }
  template <class T>
  explicit constexpr static_modint(T value_) noexcept : value(normalize(value_)) { }
  template <class T>
  explicit constexpr operator T() const noexcept { return static_cast<T>(value); }

  constexpr value_type get() const noexcept { return value; }
  constexpr value_type &extract() noexcept { return value; }
  constexpr static_modint operator - () const noexcept { return static_modint(Mod - value); }
  constexpr static_modint operator ~ () const noexcept { return inverse(*this); }

  constexpr static_modint operator + (const static_modint &rhs) const noexcept { return static_modint(*this) += rhs; }
  constexpr static_modint& operator += (const static_modint &rhs) noexcept { 
    if ((value += rhs.value) >= Mod) value -= Mod; 
    return *this; 
  }

  constexpr static_modint operator - (const static_modint &rhs) const noexcept { return static_modint(*this) -= rhs; }
  constexpr static_modint& operator -= (const static_modint &rhs) noexcept { 
    if ((value += Mod - rhs.value) >= Mod) value -= Mod; 
    return *this; 
  }

  constexpr static_modint operator * (const static_modint &rhs) const noexcept { return static_modint(*this) *= rhs; }
  constexpr static_modint& operator *= (const static_modint &rhs) noexcept { 
    value = (cover_type) value * rhs.value % Mod;
    return *this;
  }

  constexpr static_modint operator / (const static_modint &rhs) const noexcept { return static_modint(*this) /= rhs; }
  constexpr static_modint& operator /= (const static_modint &rhs) noexcept { return (*this) *= inverse(rhs); }

  constexpr bool zero() const noexcept { return value == 0; }
  constexpr bool operator == (const static_modint &rhs) const noexcept { return value == rhs.value; }
  constexpr bool operator != (const static_modint &rhs) const noexcept { return value != rhs.value; }

  friend std::ostream& operator << (std::ostream &stream, const static_modint &rhs) { return stream << rhs.value; }
  friend constexpr static_modint inverse(static_modint val) noexcept { return power(val, Mod - 2); }
  friend constexpr static_modint power(static_modint val, cover_type exp) noexcept { 
    static_modint res(1);
    for (; exp > 0; exp >>= 1, val *= val) if (exp & 1) res *= val;
    return res;
  }

};

template <uint32_t Mod>
using mint32_t = static_modint<Mod>;

/**
 * @title Static Modint
 */
#line 2 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/factorials.cpp"

#include <cstddef>
#line 6 "/Users/kodamankod/Desktop/cpp_programming/Library/algebraic/factorials.cpp"

template <class T, size_t N>
class factorials {
public:
  using value_type = T;

public:
  std::array<value_type, N + 1> fact{};
  std::array<value_type, N + 1> fact_inv{};

  factorials() {
    fact.front() = value_type(1);
    for (size_t i = 1; i <= N; ++i) {
      fact[i] = fact[i - 1] * value_type(i);
    }
    fact_inv.back() = ~fact.back();
    for (size_t i = N; i > 0; --i) {
      fact_inv[i - 1] = fact_inv[i] * value_type(i);
    }
  }

  value_type operator () (size_t n, size_t r) const {
    assert(n <= N);
    assert(n >= r);
    return fact[n] * fact_inv[n - r] * fact_inv[r];
  }
};

/**
 * @title Factorial
 */
#line 19 "main.cpp"

using i32 = int32_t;
using i64 = int64_t;
using u32 = uint32_t;
using u64 = uint64_t;

constexpr i32 inf32 = (i32(1) << 30) - 1;
constexpr i64 inf64 = (i64(1) << 62) - 1;

using m32 = mint32_t<1000000007>;
factorials<m32, 2000> fact;

int main() {
  i32 S;
  std::cin >> S;
  m32 ans;
  for (auto len: range(1, S + 1)) {
    if (len * 3 <= S) {
      ans += fact(S - len * 3 + len - 1, len - 1);
    }
  }
  std::cout << ans << '\n';
  return 0;
}


Measured memory_bytes: 3656