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#include <bits/stdc++.h>
#define REP(i,n) for(int _n=(n), i=0;i<_n;++i)
#define FOR(i,a,b) for(int i=(a),_b=(b);i<=_b;++i)
#define FORD(i,a,b) for(int i=(a),_b=(b);i>=_b;--i)
using std::vector;

void init_io() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);
}

template<unsigned MOD>
class Modulo {
 public:
  Modulo(unsigned x=0):v(x) {}
  unsigned get() const { return v; }
  Modulo operator+(Modulo b) const {
    unsigned res = v+b.v;
    if (res >= MOD) res -= MOD;
    return res;
  }
  void operator+=(Modulo b) { *this = *this + b; }
  Modulo operator-(Modulo b) const { return *this + Modulo(MOD-b.v); }
  void operator-=(Modulo b) { *this = *this - b; }
private:
  unsigned v;
};
using Mod = Modulo<1'000'000'007>;

vector<int> boxes;

void read_input() {
  size_t n;
  std::cin >> n;
  boxes.reserve(n);
  REP(i,n) {
    int x;
    std::cin >> x;
    boxes.push_back(x);
  }
  std::sort(boxes.begin(), boxes.end());
}

Mod calc_ways() {
  int range = std::max(2, boxes.back());
  std::vector<Mod> ways_at_least(range);
  std::vector<Mod> new_ways_at_least(range);
  ways_at_least[0] = 1;
  for(int box : boxes) {
    // need at least box-1 previously
    REP(x, range) {
      new_ways_at_least[x] = ways_at_least[x] + ways_at_least[std::max(box-1, x-box)];
    }
    ways_at_least.swap(new_ways_at_least);
  }
  return ways_at_least[1];
}

int main() {
  init_io();
  read_input();
  Mod res = calc_ways();
  std::cout << res.get() << "\n";
}