#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, j = 2, i, p;
  long long int k;
  cin >> n >> k;
  p = n;
  long long int b, sum = 0, m;
  int a[n], t = -1;
  for (i = 1; i <= n; i++) {
    cin >> b;
    if (i != 1) {
      m = sum - (j - 1) * (p - j) * b;
      if (m < k) {
        a[++t] = i;
        p--;
      } else {
        sum += b * (j - 1);
        j++;
      }
    }
  }
  for (i = 0; i <= t; i++) {
    cout << a[i] << "\n";
  }
  return 0;
}
