#include <bits/stdc++.h>

using i16 = std::int16_t;
using i32 = std::int32_t;
using i64 = std::int64_t;
using usize = std::size_t;
using namespace std;

#define rep(i, max) for(i32 i = 0; i < (i32)max; ++i)
#define loop while(true)
#define allOf(collection) collection.begin(), collection.end()

unique_ptr<string> readLine() { unique_ptr<string> line(new string()); getline(cin, *line); return line; }
template<typename T1, typename T2> pair<T1, T2> readPair() { T1 res1; cin >> res1; T2 res2; cin >> res2; readLine(); return make_pair(res1, res2);}
template<typename T> unique_ptr<vector<T>> readVector(usize num, bool isForIndex = false) { unique_ptr<vector<T>> list(new vector<T>(num)); rep(i, num) { cin >> (*list)[i]; if(isForIndex) --(*list)[i]; } readLine(); return list; }
void readValues() { readLine(); }
template<typename H, typename... T> void readValues(H& head, T&&... tails){ H a; cin >> a; head = a; readValues(forward<T>(tails)...); }
void writeLine() { cout << endl; }
template<typename T> void write(const T& arg) { cout << arg; }
template<typename T> void writeLine(const vector<T>& arg){ if(arg.empty()) { writeLine(); return; } write(arg[0]); for(int i = 1; i < arg.size(); ++i){ write(" "); write(arg[i]); } writeLine(); }
template<typename T> void writeLine(const T& arg) { cout << arg << endl; }
void recursiveCombination(vector<i32>& indexes, i32 s, i32 rest, function<void(vector<i32>&)> f) { if (rest == 0) { f(indexes); } else { if (s < 0) return; recursiveCombination(indexes, s - 1, rest, f); indexes[rest - 1] = s; recursiveCombination(indexes, s - 1, rest - 1, f); } }
void foreachWithCombination(i32 n, i32 k, function<void(vector<i32>&)> f) { auto indexes = vector<i32>(k); recursiveCombination(indexes, n - 1, k, f); }
void foreachWithPermutaton(i32 n, function<void(vector<i32>&)> f) { auto indexes = vector<i32>(); indexes.reserve(n); rep(i, (usize)n) indexes.push_back(i); do f(indexes); while (next_permutation(allOf(indexes))); }
void foreachWithPermutaton(i32 n, i32 k, function<void(vector<i32>&)> f){ foreachWithCombination(n, k, [=](vector<i32>& combIndexes){ foreachWithPermutaton(k, [=](vector<i32>& permIndexes){ auto indexes = vector<i32>(); indexes.reserve(k); rep(i, (usize)k){ indexes.push_back(combIndexes[permIndexes[i]]); } f(indexes); }); }); }
void program();
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    program();
    cin.get();
}

constexpr i64 mod = 1'000'000'007;
constexpr i32 ncrMax = 2000;
i64 fac[ncrMax], finv[ncrMax], inv[ncrMax];

void nCrInit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < ncrMax; i++){
        fac[i] = fac[i - 1] * i % mod;
        inv[i] = mod - inv[mod%i] * (mod / i) % mod;
        finv[i] = finv[i - 1] * inv[i] % mod;
    }
}

i64 nCr(i32 n, i32 r) {
    if (n < r) return 0;
    if (n < 0 || r < 0) return 0;
    return fac[n] * (finv[r] * finv[n - r] % mod) % mod;
}

void program() {
    i32 s;
    readValues(s);
    i32 rest = s % 3;
    i64 result = 0;

    nCrInit();

    for(i32 length = s / 3; length >= 1; --length, rest += 3) {
        result += nCr(rest + length - 1, length - 1);
        result %= mod;
    }
    writeLine(result);
}

Measured memory_bytes: 3700