#include <bits/stdc++.h>
using namespace std;
long long n, a[200001], k, curr, currlength;
vector<int> ans;
int main() {
  ios_base::sync_with_stdio(false);
  cin >> n >> k;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  int i = 1;
  curr = 0;
  currlength = n;
  long long currmul = 1;
  while (i < n) {
    long long temp = curr - (currmul) * (currlength - currmul - 1) * a[i];
    if (temp < k) {
      ans.push_back(i + 1);
      currlength--;
    } else {
      curr += (currmul)*a[i];
      currmul++;
    }
    i++;
  }
  for (int i = 0; i < ans.size(); i++) {
    cout << ans[i] << endl;
  }
  return 0;
}
