#include <bits/stdc++.h>
using namespace std;
vector<int> v;
int main() {
  int n;
  cin >> n;
  int s = 0;
  int a[n];
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    s += a[i];
  }
  v.push_back(0);
  int sum = a[0];
  for (int i = 1; i < n; i++) {
    if (a[0] >= 2 * a[i]) {
      sum += a[i];
      v.push_back(i);
    }
    if (sum * 2 > s) break;
  }
  if (sum * 2 > s) {
    cout << v.size() << "\n";
    for (int i = 0; i < v.size(); i++) {
      cout << v[i] + 1 << " ";
    }
  } else
    cout << 0;
}
