#include <bits/stdc++.h>
using namespace std;
int main() {
  int T;
  cin >> T;
  int sum = 0;
  vector<int> arr;
  while (T--) {
    int x;
    cin >> x;
    arr.push_back(x);
    sum += x;
  }
  vector<int> ans;
  ans.push_back(1);
  int ans_sum = arr[0];
  for (int i = 1; i < arr.size(); i++) {
    if (arr[i] * 2 <= arr[0]) {
      ans.push_back(i + 1);
      ans_sum += arr[i];
    }
  }
  if (sum >= ans_sum * 2)
    cout << 0 << endl;
  else {
    cout << ans.size() << endl;
    ;
    for (int i = 0; i < ans.size(); i++) {
      cout << ans[i] << " ";
    }
    cout << endl;
  }
}
