#include <bits/stdc++.h>
using namespace std;
const double PI = acos(-1.0);
template <class _T>
inline string tostr(const _T& a) {
  ostringstream os("");
  os << a;
  return os.str();
}
long long val[200200], n, k, m, soma;
long long calc(int pos) {
  return soma - (pos - m - 1) * ((n - m) - (pos - m)) * val[pos];
}
int main() {
  cin >> n >> k;
  for (int i = 1; i <= n; i++) {
    cin >> val[i];
  }
  soma = 0;
  m = 0;
  for (long long i = 2; i <= n; i++) {
    long long tem = calc(i);
    if (tem < k) {
      cout << i << endl;
      m++;
    } else {
      soma += (i - 1 - m) * val[i];
    }
  }
  return 0;
}
