#include <bits/stdc++.h>
using namespace std;
long long a[2000000], d[2000000], val[2000000];
int main() {
  long long N, K;
  long long i, k, n, bef;
  scanf("%I64d%I64d", &N, &K);
  for (i = 1; i <= N; i++) scanf("%I64d", a + i);
  d[1] = 0;
  val[1] = 0;
  bef = a[1];
  n = N;
  for (i = k = 2; i <= N; i++) {
    val[k] = val[k - 1] + bef * (k - 2);
    d[k] = val[k] - (k - 1) * a[i] * (n - k);
    if (d[k] < K) {
      printf("%I64d\n", i);
      n--;
    } else {
      bef = a[i];
      k++;
    }
  }
  return 0;
}
