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#include <bits/stdc++.h>
using namespace std;

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);

  int n, max_s = 0; cin >> n;
  const int mod = 1e9 + 7;
  vector<int> v(n);
  
  for (auto &x : v) {
    cin >> x;
    max_s += x;
  }
  
  sort(v.begin(), v.end());
  vector<vector<int>> dp(2, vector<int>(max_s+1));
  if (v[0] != 1) {
    cout << 0;
    return 0;
  }

  dp[0][1] = 1;

  for (int i = 1; i < n; ++i) {
    dp[1] = dp[0];
    dp[1][1] += v[i] == 1;
    for (int s = v[i]-1; s <= max_s-v[i]; ++s) {
      dp[1][s+v[i]] = (dp[1][s+v[i]] + dp[0][s]) % mod;
    }
    swap(dp[0], dp[1]);
  }


  int ans = 0;
  for (int i = 1; i <= max_s; ++i)
    ans += dp[0][i];
  ans %= mod;
  cout << ans << '\n';
}

// 5
// 1 2 4 4 7

// 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
// 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18