#include <bits/stdc++.h>
#pragma GCC optimize("O3")
using namespace std;
int n, v[102], ss;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cin >> n;
  int sum = 0;
  for (int i = 1; i <= n; ++i) cin >> v[i], sum += v[i];
  ss = v[1];
  vector<int> vv;
  vv.push_back(1);
  for (int i = 2; i <= n; ++i)
    if (v[i] * 2 <= v[1]) ss += v[i], vv.push_back(i);
  int px = sum / 2 + 1;
  if (ss < px) {
    cout << 0;
  } else {
    cout << vv.size() << '\n';
    for (int i = 0; i < vv.size(); ++i) cout << vv[i] << " ";
  }
  return 0;
}
