#include <bits/stdc++.h>
using namespace std;
long long a[920011];
int main() {
  long long temp, cur, p, li;
  long long n, k, num;
  while (cin >> n >> k) {
    for (int j = 1; j <= n; j++) cin >> a[j];
    p = 0;
    cur = 1;
    num = n;
    li = 1;
    for (int j = 1; j < n; j++) {
      temp = p + li * (li + 1) * a[j + 1] - num * li * a[j + 1];
      temp = p - (num - li - 1) * li * a[j + 1];
      if (temp < k) {
        cout << j + 1 << endl;
        num--;
      } else {
        cur = j + 1;
        p = p + a[j + 1] * li;
        li++;
      }
    }
    cout << endl << endl;
  }
  return 0;
}
