#include <bits/stdc++.h>
using namespace std;
int main() {
  int N;
  long long K;
  cin >> N >> K;
  vector<int> a;
  a.push_back((int)-1);
  int x;
  for (int n = 0; n < N; ++n) {
    scanf("%d", &x);
    a.push_back(x);
  }
  long long Sum = 0;
  long long Count = 0;
  for (int n = 1; n <= N; ++n) {
    long long temp = Sum - ((n - Count - 1) * 1ll * (N - n) * 1ll * a[n]);
    if (temp < K) {
      printf("%d\n", n);
      Count++;
    } else {
      Sum += (long long)a[n] * (long long)(n - Count - 1);
    }
  }
  return 0;
}
