#include <bits/stdc++.h>
using namespace std;
int a[200010];
int main() {
  int n, k;
  cin >> n >> k;
  for (int i = 0; i < n; i++) cin >> a[i];
  long long sum = 0, counter = 1, current = n, d;
  for (int i = 1; i < n; i++) {
    d = sum - (current - counter - 1) * a[i] * (counter);
    if (d < k) {
      cout << (i + 1) << endl;
      current--;
    } else {
      sum += a[i] * counter;
      counter++;
    }
  }
}
