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#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;

#define M 1000000007
#define A 5000

int n;
vector<int> nums;

int C[A][A];
int P[A + 1];

int foo(int idx, int cumsum) {
  int out;
  if (idx == n || nums[idx] > cumsum + 1) {
    return 0;
  }
  if (cumsum >= A - 1) {
    // every forward subset is ok so return 2^(n - idx)
    return (P[n - idx] - 1) % M;
  }
  if (C[idx][cumsum] != -1) {
    return C[idx][cumsum];
  }

  out = 1;
  out += foo(idx + 1, cumsum);
  out += foo(idx + 1, cumsum + nums[idx]);
  out %= M;
  C[idx][cumsum] = out;
  return out;
}

int main() {
  int i, j;

  for (i = 0; i < A; ++i) {
    for (j = 0; j < A; ++j) {
      C[i][j] = -1;
    }
  }
  P[0] = 1;
  for (i = 1; i <= A; ++i) {
    P[i] = (P[i - 1] * 2) % M;
  }

  ios_base::sync_with_stdio(0);
  cin >> n;
  nums.reserve(n);
  for (i = 0; i < n; ++i) {
    int a;
    cin >> a;
    nums.push_back(a);
  }
  sort(nums.begin(), nums.end());
  cout << foo(0, 0) << endl;
  return 0;
}