// Slower C++ solution:
#include <bits/stdc++.h>

#define ALL(x) (x).begin(), (x).end()

#define RALL(x) (x).rbegin(), (x).rend()

#define FSP(x) fixed << setprecision(x)

using namespace std;

using ll = long long;

constexpr ll INF = LLONG_MAX;

constexpr long double PI = acosl(-1);

void Yes() {cout << "Yes\n";}

void No() {cout << "No\n";}

void YES() {cout << "YES\n";}

void NO() {cout << "NO\n";}



#include <iostream>

#include <vector>



/*	NOTICE : followings requires template argument to be prime

		- use of modinv

		- division by modint

		- use of factorial_inv

*/



/*	verified : 2020/07/30

		AtCoder, Knapsack for All Subsets

		https://atcoder.jp/contests/abc169/tasks/abc169_f

		AtCoder, Bouquet

		https://atcoder.jp/contests/abc156/tasks/abc156_d

*/



template<long long P>

long long modinv(long long n) {

	long long a = P, u = 1, v = 0;

	while (a) {

		long long t = n / a;

		n -= t * a;

		std::swap(n, a);

		u -= t * v;

		std::swap(u, v);

	}

	u %= P;

	if (u < 0) u += P;

	return u;

}



template<long long M>

struct modint {

	long long val;



	modint<M>(long long right) : val(right) {sub(val);}

	modint<M>() {val = 0;}



	void sub(long long &n) {

		if (n < 0) {

			long long m = (-n) % M;

			n = M - m;

		}

		else n %= M;

	}



	modint<M> operator+ (modint<M> right) {return (this -> val) + right.val;}

	modint<M> operator+ (long long right) {sub(right); return (this -> val) + right;}

	modint<M> operator- (modint<M> right) {return (this -> val) - right.val;}

	modint<M> operator- (long long right) {sub(right); return (this -> val) - right;}

	modint<M> operator* (modint<M> right) {return (this -> val) * right.val;}

	modint<M> operator* (long long right) {sub(right); return (this -> val) * right;}

	modint<M> operator/ (modint<M> right) {return *this * modinv<M>(right.val);}

	modint<M> operator/ (long long right) {sub(right); return *this * modinv<M>(right);}



	void operator+= (modint<M> right) {*this = *this + right;}

	void operator+= (long long right) {*this = *this + right;}

	void operator-= (modint<M> right) {*this = *this - right;}

	void operator-= (long long right) {*this = *this - right;}

	void operator*= (modint<M> right) {*this = *this * right;}

	void operator*= (long long right) {*this = *this * right;}

	void operator/= (modint<M> right) {*this = *this / right;}

	void operator/= (long long right) {*this = *this / right;}



	modint<M>& operator++ () {*this += 1; return *this;}

	modint<M> operator++ (int) {*this += 1; return *this - 1;}

	modint<M>& operator-- () {*this -= 1; return *this;}

	modint<M> operator-- (int) {*this -= 1; return *this + 1;}

};



std::vector<long long> factorial;

std::vector<long long> factorial_inv;



template<long long P>

constexpr void make_table(long long n) {

	factorial.resize(n + 1, 1); factorial_inv.resize(n + 1, 1);

	for (long long i = 2; i <= n; i++) {

		factorial[i] = factorial[i - 1] * i % P;

	}

	factorial_inv[n] = modinv<P>(factorial[n]);

	for (long long i = n - 1; i >= 0; i--) {

		factorial_inv[i] = factorial_inv[i + 1] * (i + 1) % P;

	}

}



template<long long P>

modint<P> permutation(long long n, long long r) {

	if (n <= factorial.size()) {

		modint<P> a = factorial[n], b = factorial_inv[n - r];

		return a * b;

	}

	else {

		std::cerr << "attention : factorial table is not constructed" << '\n';

		modint<P> ret = 1;

		for (long long i = 0; i < r; i++) ret *= n - i;

		return ret;

	}

}



template<long long P>

modint<P> combination(long long n, long long r) {

	r = std::min(r, n - r);

	if (n <= factorial.size()) {

		return permutation<P>(n, r) * factorial_inv[r];

	}

	else {

		std::cerr << "attention : factorial table is not constructed" << '\n';

		modint<P> ret = 1;

		for (long long i = 0; i < r; i++) {

			ret *= n - i;

			ret /= i + 1;

		}

		return ret;

	}

}



template<long long M>

modint<M> modpow(long long a, long long n) {

	a %= M;

	if (n == 0) return 1;

	if (a == 0) return 0;

	if (a == 1) return 1;

	long long b = 1, cnt = 0;

	while (b < M && cnt < n) {

		b *= a;

		cnt++;

	}

	modint<M> ret;

	if (b < M) ret = b;

	else {

		b %= M;

		ret = modpow<M>(b, n / cnt) * modpow<M>(a, n % cnt);

	}

	return ret;

}



template<long long M>

modint<M> modpow(modint<M> a, long long n) {

	return modpow<M>(a.val, n);

}



template<long long M>

std::ostream &operator<< (std::ostream &out, modint<M> tgt) {out << tgt.val; return out;}



int main() {

	ios::sync_with_stdio(false);

	cin.tie(nullptr);

	constexpr ll P = 1000000007;

	//constexpr ll P = 998244353;



	ll s;

	cin >> s;

	make_table<P>(1e5);

	modint<P> ans = 0;

	for (ll i = 1; i < 700; i++) {

		if (i * 3 > s) break;

		ll rest = s - i * 3;

		ans += combination<P>(rest + i - 1, rest);

	}

	cout << ans << endl;

}

// Faster C++ solution for the same problem (measured speedup: 3.504715997450515x):
#include <iostream>

#include <vector>



long long modinv(long long n, long long P) {

	long long a = P, u = 1, v = 0;

	while (a) {

		long long t = n / a;

		n -= t * a;

		std::swap(n, a);

		u -= t * v;

		std::swap(u, v);

	}

	u %= P;

	if (u < 0) u += P;

	return u;

}



template<long long MOD> struct modint {

	long long value;

	void f() {

		if (0 <= value && value < MOD) return;

		value %= MOD;

		if (value < 0) value += MOD;

	}

	modint(long long n) : value(n) {f();}

	modint<MOD> operator+(modint<MOD> right) {

		modint<MOD> ret = (this -> value) + right.value;

		return ret;

	}

	modint<MOD> operator-(modint<MOD> right) {

		modint<MOD> ret = (this -> value) - right.value;

		return ret;

	}

	modint<MOD> operator*(modint<MOD> right) {

		modint<MOD> ret = (this -> value) * right.value;

		return ret;

	}

	modint<MOD> operator/(modint<MOD> right) {

		modint<MOD> ret = (this -> value) * modinv(right.value, MOD);

		return ret;

	}

	modint<MOD> operator+=(modint<MOD> right) {return *this = *this + right;}

	modint<MOD> operator-=(modint<MOD> right) {return *this = *this - right;}

	modint<MOD> operator*=(modint<MOD> right) {return *this = *this * right;}

	modint<MOD> operator/=(modint<MOD> right) {return *this = *this / right;}

	bool operator==(modint<MOD> right) {return ((this -> value) == right.value);}

	bool operator!=(modint<MOD> right) {return ((this -> value) != right.value);}

};

template<long long MOD> modint<MOD> operator+(long long left, modint<MOD> right) {

	return right + left;

}

template<long long MOD> modint<MOD> operator-(long long left, modint<MOD> right) {

	return right * -1 + left;

}

template<long long MOD> modint<MOD> operator*(long long left, modint<MOD> right) {

	return right * left;

}

template<long long P> modint<P> operator/(long long left, modint<P> right) {

	return modinv(right.value, P) * (left % P);

}



template<long long MOD> modint<MOD> modpow(modint<MOD> a, long long n) {

	if (n == 0) return 1;

	if (a == 0) return 0;

	modint<MOD> ret = a;

	long long cnt = 1;

	while (cnt * 2 <= n) {

		ret *= ret;

		cnt *= 2;

	}

	return ret * modpow<MOD>(a, n - cnt);

}



long long modpow(long long a, long long n, long long MOD) {

	if (n == 0) return 1;

	if (a == 0) return 0;

	long long ret = a % MOD;

	long long cnt = 1;

	while (cnt * 2 <= n) {

		ret *= ret; ret %= MOD;

		cnt *= 2;

	}

	return ret * modpow(a, n - cnt, MOD) % MOD;

}



std::vector<long long> factorial;

std::vector<long long> factorial_inv;



template<long long P> void make_table(int n) {

	factorial.resize(n + 1, 1); factorial_inv.resize(n + 1, 1);

	for (int i = 1; i <= n; i++) factorial[i] = factorial[i - 1] * i % P;

	factorial_inv[n] = modinv(factorial[n], P);

	for (int i = n - 1; i >= 0; i--) factorial_inv[i] = factorial_inv[i + 1] * (i + 1) % P;

}



template<long long P> modint<P> permutation(int n, int r) {

	if (n <= factorial.size()) return factorial[n] * factorial_inv[n - r];

	std::cerr << "attention : factorial table is not constructed" << std::endl;

	r = std::min(r, n - r);

	modint<P> ret = 1;

	for (int i = 0; i < r; i++) ret *= n - i;

	return ret;

}



template<long long P> modint<P> combination(int n, int r) {

	if (n <= factorial.size()) return permutation<P>(n, r) * factorial_inv[r];

	std::cerr << "attention : factorial table is not constructed" << std::endl;

	r = std::min(r, n - r);

	modint<P> ret = 1;

	for (int i = 0; i < r; i++) {

		ret *= n - i;

		ret /= i + 1;

	}

	return ret;

}



template<long long MOD> std::ostream& operator<<(std::ostream& os, const modint<MOD>& target) {

	os << target.value; return os;

}



int main() {

	constexpr int P = 1000000007;

	int s;

	std::cin >> s;

	modint<P> ans = 0;

	make_table<P>(2000);

	for (int i = 1; i * 3 <= s; i++) {

		ans += combination<P>(s - i * 3 + i - 1, i - 1);

	}

	std::cout << ans << '\n';

}