#include <bits/stdc++.h>
using namespace std;
long long now, a[200005];
int n, k, nub, last, g;
int main() {
  scanf("%d %d", &n, &k);
  g = n;
  for (int i = 1; i <= n; i++) {
    scanf("%I64d", &a[i]);
    nub++;
    if (now + last * (nub - 2) - a[i] * (g - nub) * (nub - 1) < k) {
      printf("%d\n", i);
      g--;
      nub--;
    } else {
      now += last * (nub - 2);
      last = a[i];
    }
  }
}
